Conference 7.286::home_work

    Yes, I have many times in the past. Sometimes it's because the load
    is too heavy and dropping down to a lower charge may help. On the
    otherhand, power nailing has always been a problem, at least with
    me. I prefer to use exspandable anchors, but if you have alot to
    do maybe power nailing is your only choice. Good luck!
    

    I have a split entry which I bought with the lower level unfinished.
    I did exactly the same as you but did not have much problem.
    
    I used the remington power nailer.  This one is a single shot machine
    which you hit with a hammer to fire.  I first tried using the green
    loads but could not get them to penetrate into the concrete
    consistantly.  I then switched to the yellow loads with a greater
    sucess.
    
    For my floor, I ran preassure treated 2x4's flat on the floor and power
    nailed them to the concrete.   I spaced them so that every edge of the
    plywood subfloor would half cover a 2x4.  I also ran at least one 2x4
    down the middle under each sheet of plywood.  I filled the space
    between the 2x4's with rigid insulation, then covered the whole floor
    with a vapor barier before adding the 3/4" plywood which I screwed
    into the 2x4's at about every 6" with 1.5" drywall screws.  I covered
    the floor with a good quality pad and very heavy carpet (47oz).
    The final result is a floor which is bone dry and warm.  I wanted
    to be extra sure here because one of the rooms is the playroom for
    the kids.  In my mind, the extra work was worth the effort.
    
    Jim Pappas
    

    Jim,
    
    	I have the same idea for my basement floor.  I also had to use
    	the yellow loads to get the nail to go through the 2 by and
     	into the concrete.  It looks to me that this concrete floor
    	was made with more cement than sand in its mix.  It's very 
    	brittle.  Did you use the same type of nail?  I'm wondering
    	if they may have a flutted-nail which might work better.
    
    	-Tony
    

    I recently began studding out my basement and I remember 6 months
    ago...wondering how I was going to fasten the bottom plate into
    the concrete floor. I've been using pressure treated 2x4's for the
    bottom plate and last week it was time, all I had on hand was cement
    nails and I heard not many have had good luck with these. 
    
    I drilled a pilot hole, put the cement nail in and tapped it till
    it met the floor, I used a sledge hammer held high over my head...
    came down and wacked the @#*& out of it. I was quite suprised, the
    nail did penetrate the floor. Only a couple went in on the 1st wack
    most took 2-3. I don't doubt that the concrete chipped abit around
    the nail but holding the 2x4 tight against the floor seemed to help.  
    Yes, there were a few that didn't make it....

    Mark 

    I second the previous BRIEF message about using construction adhesive.
    For some reason, people view this as less than solid. NOT TRUE.
    I finished my ENTIRE first floor studding this way (on the
    recommendation of a contractor). It IS within code, it is VERY easy
    to do, VERY SOLID, and most important: IT DOES NOT CRACK THE CEMENT
    WHATSOEVER so the water seal remains intact. I have been told that
    ANY penetration into a cement floor can potentially lead to
    cracking the REST of the cement and also water problems.
    
    Mark
    

    Be careful when hitting concrete nails with a hammer.  Pieces can
    break off and become missles.  Use safety glasses..

    Sorry I overlooked that point....SAFETY GLASSES are a must when
    working with any type of saws or power equip. or banging on cement
    nails into concrete. I've been religious in my use of safety glasses
    for 'bout 7 years now during most shop operations. Unfortuneatly
    I, like others, must learn the hard way first....

    Another vote for construction adhesive. About 10 years ago I bought
    some old kitchen cabinets at a garage sale for my shop. I glued
    1x3 to the concrete walls with construction adhesive and the next
    day hung the cabinets. They are still there, FULL of heavy  tools
    and 'shop stuff' and have never shown the slightest sign of moving.
    And the load is in shear, the worst case for this kind of glue.
    
    Ron
    

    
    	So it sounds like the floor has to be treated with a water
    	proof sealer and then, the adhesive can be put down on top
    	of that.  What happens if water gets to it before or after it
    	dries?  Is Thompsons's Water Sealer the right stuff to use?

    RE: .2 .6 .9
    
    OK, I'll bite (someone has to do it).  Where does one get "Construction
    Adhesive"?  [I know, I know SPAGS - right?] Is that what it is *really*
    called?  I have heard of (and used) many types of adhesives, but don't
    think I've ever run across construction adhesive (or if I did, didn't
    know what its use was).  Sounds like neat stuff.  There have been
    several things I could have used it for already. 
    
    BTW.  I use a 3M "Industrial Adhesive" for gluing felt to metal which
    works *VERY* well.  I can post the 3M number if any one is interested.
    
    -Bob

    That is good input on the adhesive.  On the floor, you do not really
    need much strength.  In fact, now that my plywood is screwed to the
    2x4's with about a billion screws (actually billions and billions), I
    dont think it would really make any difference if the 2x4's were nailed
    down or not.
    
    As far as water problems, and possible cracking, concrete is very
    porous and too my best knowledge, water will pass through even if
    it is not cracked.  However, with preasure treated 2x4's, styrofoam
    insulation, and a good vapor barier, I dont care if Old Faithful
    erupts every hour under there, my floor is staying dry and warm.
    However, I am very lucky and my basement has always been bone dry.
    
    One more remark,  I ran my vapor barrier about 4 feet up the walls
    and overlapped the vapor barrier in the walls.  I prefer to take
    no chances.
    
    Jim Pappas

    re: 13
    
    Did you use the "Energy Shield" rigid insulation or the cheaper
    polystyrene foam panels for your floor insulation?

Almost any hardware store will have construction adhesive.  It comes in tubes 
like caulk.

Paul

    "PL400" (Don't know who makes it ) is the best construction adhesive
    I've seen.  Unfortunately most DIY places only stock "PL200" which
    is not quite so heavy-duty.   I would say PL400, Liquid Nails, and
    PL200 are the rank from strongest to weakest.
    
    Jim

    I've gone through this twice so far in my house, and have a third
    floor coming up.  Most of what has been said so far is pretty on
    track, but there are a few bits and pieces that should be added:
    
    Usually you use 1x3 (called 'strapping') rather than 2x, because
    you want them to be able to 'give' a little over slight imperfections
    in the floor; 2x's just don't give, especially if they are pressure
    treated.  What you do is:
    	1. Mark out the 16" spacing (so that the plywood goes down in
    the right places.
    	2. as you get ready for each course, paint some tar or roofing
    cement on the area you are putting the 1x3, for a width of about
    5".  This protects the wood itself from rot.
    	3. nail down or glue down the 1x3 (I prefer nails).
    	4. after all of the 1x3's are down, lay in the rigid insulation.
     Styrofoam is just passable; the energy shield stuff is much better.
    comes in 4x8 sheets, and cuts with a sheetrock knife.  Lay this
    between (not covering) the 1x3's, and for a thickness equal to the
    1x3s.
    	5. Now lay over all of the above a vapor shield of at least
    3 mil poly...  I second the motion for continuing it up the walls
    if you are doing walls at the same time.  Tape it off where you
    must have seams, and do a lot of overlapping.
    	6. Now lay the second course of strapping, but just use 1 1/2"
    underlayment nails (not common nails), right over the first layer.
    	7. Put in the second layer of rigid insulation.
    	8. Now put down the underlayment, long side parallel to the
    strapping.  nail down with 1 3/4" underlayment nails.  Be sure that
    all underlayment seams on the long side are centered on the strapping.
    
    This will give you a tight, insullated, waterproof floor, that will
    never creak or warp.
    
    On the subject of getting those &*&*& nails into the concrete: Yes
    there are fluted nails, but only for hand application (that was
    what the guy with the sledge used).  The work fine, but use a LOT
    of energy (yours).  The power hamer from Rockwell is on my list
    of wasted money (anyone want to buy it?), as it does not have enough
    power to shoot the nails worth a *(*(.  Better is the Powder Actuated
    Gun sold by Rockwell (Spag's sells for 179, Taylor Rentals rents
    for abut 22/day).  The hammer version still takes a lot of your
    time and energy.  The gun has more power, and takes very little
    of your energy.  You can lay all of the strapping for a 10x20 room
    in a day.  I did it in a couple of hours, but that was on a floor
    that was already sealed, so I didn't have to play around with the
    tar.
    
    The comment on cracking the slab is important:  usually a carpenter's
    motto is 'the more nails the better' and usually that is a good
    philosophy.  NOT WITH CONCRETE NAILING.  Don't put them any closer
    than 18" - 24" is just fine.  It only needs to go into the slab
    for close to an inch.  This is why the hand-driven nails are fluted,
    and is also why the powder tool is better:  it drives the nail in
    quickly.  The fast it goes it, the less of a problem with cracking,
    and the more holding action given by the concrete onto the nail.
    
    Good luck Mr. Briggs.
    -reed
    

    Re. 17 Item #8
    
    Plywood should be layed at RIGHT ANGLES to the strapping/floor joists/
    rafters/wall studs etc. for maximum strength and stiffness. The
    only exception to this rule would be decorative materials (T-111,
    paneling...). For a real strong sub-floor use 3/4 inch Tongue and
    Groove Plywood. 
    
    Charly

    re .18
    
    I was going to say the same thing about the direction in which to
    lay the plywood.  Also you should stagger the short seams.
    
    Rich

    I need to drill a 6-8" hole in my concrete garage floor to 
    install a drain.  My question is what to use to make the hole.
    I know i can use a hand chisel and a hammer but my knuckles 
    probably wouldn't last and my wife is smarter than that.
    
    Someone mentioned renting an electric jack hammer at the local
    rental outfit that is smaller than the "real" ones and pretty
    easy to use.
    
    Has anybody ever used one of these or have any other suggestions?
    
    

    you could probably rent a hammer drill from a place like Taylor
    Rental, scribe the circumference of the hole on the floor and then
    drill around the line and then break away the rest of the hole.
    
    This shouldn't take that long at all. (15-20min)
    
    
    
    Royce

    There is also a hole saw bit for the hammer drills.
    
    I recently had a 5" hole drilled through a foundation wall. Using 
    the "Hilti" (electric hammer/drill) and the hole saw bit we had a 
    perfect hole in about 15 minutes. Check with the rental shops and 
    see if they have the Hilti and a drill bit for the size that you want.
                                            
    Charly

    leave out the chisle, just use the hammer.  No, this is not a joke.
    I just had a plumber in doing the rough plumbing on my addition,
    and also had him do the plumbing for a 1/2 bath in the existing
    cellar area.  That meant running a drain under the foundation over
    to the stack (about 4' away, carefully planned).
    
    All he had to do was use a 50# sledge, and wack at the floor for
    a couple of minutes, to get the basic hole done, and then go after
    the edges until it was the right size (he then dug under the floor
    with something to reach the similar hole he did at the stack, rather
    than tear up the entire stretch.
    
    In any event, you are not going to get a clear hole.  It will be
    quite rough, and need re-cementing with you are through, so don't
    worry about whether the edges are exactly the right shape, etc.
    
    Taylor's rents the various tools mentioned in .1 and .2, by the
    way.
    
    Good luck, Mr. Briggs
    

re:2

If you can drill a 5" hole through a foundation in 5 minutes, why do 
people pay so much do say through them.  I'd think a series of holes 
would allow you to produce a reasonable opening, assuming you then face 
the somewhat rough edges with some wood.  Sounds a lot cheaper than the 
$300+ figures mentioned earlier in here somewhere.

Anybody ever tried this?

-mark

    Reading your problem, I'm going to mention 2 other problems that
    might affect you. first, since this is a garage floor, I would have
    to assume that it has been reinforced by steel mesh. 2nd, once you
    drill the hole, were is the water going?. If you are connecting
    to an existing drain, no problem. But if this is new, that means
    that you must also drill though the wall of the garage to take the
    water out, or build a dry well under the garage floor. This last
    dry well is not that great, since it will tend to undermine the
    rest of the floor. Sorry,didn't mean to rain on your parade, I just
    wanted to mention these potential problems. The rental shops have
    what you need and will do the job. 
    						Good Luck
    
    

re:4
    
    I assume you are refering to cutting a door opening into a concrete
    wall like this,
                                            
    _____________________________________
               O      O
               O      O
               O      O
               O      O
               O      O
               O      O
    ___________OOOOOOOO___________________
    
    Let's see.... I have 7 1/2 foot high walls, that's 90 inches
    divided by 5 inches = 18 holes per side. A 3 1/2 foot opening would
    be another 8 holes. That's 44 holes times 15 minutes per hole for
    a total of 660 minutes or 11 HOURS of continuous drilling. That's
    a lot of work for YOU the DRILL and the BIT. And when you done,
    you still have a very rough opening to frame. 
    
    If you want to DYI, I think a 1" chisel bit would produce faster
    and neater results than the hole saw approach. If you call the Pros,
    they will bring in an expensive concrete cutting saw, but the resulting
    cut will probably be smoother than the face of the concrete wall.
    
    The semi-Pro DYI approach is to rent a gas power circular blade concrete
    cutting saw. I've heard that these are neat but slow going. Which
    means you have to hold up a heavy vibrating saw for a long time.
    The depth of cut also requires cutting from both sides and maybe
    even chiseling out the middle couple inches.
    
    All three methods make a BIG MESS!
    
    FYI, I have plans to cut an opening in a wall this spring and I'm
    still debating the three methods.
    
    Charly
                                                             
    

    RE: .3
    
    I would like to know whom you hired to swing a 50 lb sledge hammer!
    
    Lawrence Taylor and William Perry?
    
    Also were do you purchase a 50 lbs sledge?
    
    Mike
    

    Does anyone have experience with a poured concrete floor *above*
    the level of an existing foundation and sill board?
    
    I'm preparing a two wall (actually two and a half, but NBD) addition
    and plan to use an 8 inch frost wall with a 4 inch floor.  Typically,
    I would expect to pour up to the level of the existing foundation,
    leaving a step in/out of the addition to the house.  In this case,
    a step up is out of the question (read the wife doesn't want a step,
    end of discussion).
    
    Thus, my solution is to flash the wood above the sill and pour the
    new floor three inches below the existing floor.  I'd then add 2 by
    x sleepers (1.5 inch), plywood (3/4 inch), and a finished floor
    (another 3/4).  That seems reasonable, I think.
    
    My concern is the likelihood of getting the new poured floor to an
    almost precise height.  I see a cement truck spewing concrete and
    then heading home; an inch high or low, especially high, causes
    problems.  Does anyone have any suggestions?
    
    It seems to me that coming within 5 to 9 inches of the existing floor
    and then laying joists to level is a waste.

    It sounds like your idea of using the flashing and and then pouring
    should be ok. As far as the hight goes, are you planinng on doing
    it or having a contractor come in? 
    
    If your hiring someone, then it shouldn't be a problem, especially if
    they are good. Just tell them that you want a level floor and show them
    where you want the top of the floor to be. They are experienced at
    determining wether you need a little more or a little less cement.
    
    If you are doing it your self... well good luck. I would try to pour
    a little low rather than high. You can always build up the hight.
    
    Charly

    With the work involved and the level floor issue, its an absolute
    contractor job to me.  Now if I can just find that good one...
    

    I agree, the foundation is a contractor job since they have the
    forms.  However, if you want to do the floor yourself, it is 
    doable.  You can pour the concrete to whatever level you need.
    
    Once the walls are in, mark them with a line that represents the
    correct height for the concrete floor.  Then using a string level,
    make a "grid" (say every 3 feet) out of 1"x1" stakes driven into
    the ground so that the top of each stake is level with the string.
    When you screed the concrete, stop when the screed board rubs the
    top of the stakes.  When floating, you will be able to make finer
    adjustments in the level of the concrete.
    
    
    Mark
    
    P.S.
    Depending on the size of the floor, you may find it easier to
    pour it in 2 parts.

    Thanks muchly; the grid and stake idea is excellent!
    
    It seems to me that Mr Naylor has some experience, so another
    question...  My floor will be 14 by 20.  Is that considered a two
    part/day pour or could I handle it in one?
    
    Once again, thanks Mark for the idea.
    

    You're welcome !  
    
    Well, a 14 x 20 slab 4 inches thick will require about 3.5 yards
    of concrete.  Since many places have a minimum delivery of 4 yards
    (or else they charge a delivery fee), you could save some money
    by doing the job in one pour.  However, that is a large area to
    float.  If you could do the job in 2 pours, it would be much easier.
    So I guess you'll have to shop around then decide if the addition
    money for the concrete is worth it.  However, if the slab is thicker
    you may not have to worry about this.
    
    If you do decide to make 2 pours, another idea would be to divide
    the area into 4 14 x 5 blocks.  One pour 1, do blocks 1 and 3; and
    blocks 2 and 4 on pour 2.  That way the width is only 5 feet instead
    of 10 - which you can easily reach across to float.  In fact this
    way, you do not need the stakes - it would be like pouring a 5'
    sidewalk.  The only consideration is frost heaving - since you now
    have 4 (or 2) sections, one may heave and your nice floor would
    not be level.  A well prepared base should prevent this.  I have worked
    with concrete and masonry quite a bit, but not in this state, so I
    think you should check with someone more familiar with pouring concrete
    in this area.

    
    Good luck,
    Mark

    That is only 280 sq ft of floor and unless you are wheeling it some
    distance it should be easily done in one pour. If you mark the walls
    with nails at the proper height (chalk does not hold up well when
    wet) you can use a 13'6'' drag board to keep the level within reason.
    Use a bull float to smooth it out and when it has reached the proper
    firmness use a bull plane to finish it off (this saves on the knees).

    Thanks again for the help and suggestions; my confidence grows.
    
    However, with two bids in, one for 550 and the other 875 (just the
    floor of course), I think I'll leave the whole foundation and floor
    job to the contractor and "save" myself for the framing...
    
    

    Despite the weather, the trench is dug and the footing and walls
    are in place.  The excavator has promised to come and backfill this
    Friday or Saturday, weather permitting.
    
    My question is what's the best base for the concrete floor?  I have
    several sugestions: pea stone, the bony gravel left over from the
    trench, sand compacted by a rented compactor, and sand thoroughly
    soaked by hose or rain.
    
    I'm leaning to using the left over gravel in that its available
    (and what the heck else can I do with it).  I figured I'd just have
    to rake it sort of smooth and be ready for the next visit by the
    cement truck.
    
    So, what should it be?
    Thanks.
    

    From what I have read, bigger is better (to a point).  Pea stone
    is ok, 3/4" is better and 1-1 1/2" is even better.  The larger stones
    provide better drainage.  As for sand, you should really not use it.
    
    
    Mark
    

    Hi all,
         I have a problem (I think), that I would like to send out to
    all of you maybe for some solutions or just information.
         On friday 15 May 87 I had my foundation floor poured.  The
    floor is 3" thick, and of course the house is on top of it.  There
    are 3 standard windows in the foundation walls and a bulkhead door
    which I keep closed.  This a.m. there was more condensation on the
    floor (not puddles, just like dew) than there was yesterday or the
    day before.
         Am I being parinoid or is this part of the drying process for
    the floor.
         Some places are light color like it is dry there but most of
    the water is ware the sun doesnt shine on it.
         Can anyone offer any suggestions, or should I start to worry?
    Also there is no plastic down under the concrete, I did not know
    about it until the floor was in already.
                                                thankx
                                                     s.f. (kathy)

	I wouldn't worry about it.  Concrete takes several weeks to
	fully cure.  In a basement it doesn't get real good air 
	circulation so it may take longer.

	The plastic would have been a good idea tho...

	-gary

There are hundreds of gallons of water that have to go somewhere.  It takes a 
couple of weeks to dry out, especially if there isn't a whole lot of 
ventilation.  Your dew is perfectly normal.  If you want to help it dry out, 
open the doors and windows as often as possible.

Paul

    Now is a good time to seal it also. My neighbor recently had a garage
    floor put in and was telling me about this sealer his cement guy
    recommended he put down. You brush this stuff on as soon as you
    can safely walk on the cement without leaving any marks, usually
    the next day!
    
    If there is any interest, I'll find out what it is and post it here.

    Charly
    

    re. 3
         I am unsure that I understand what it is you are telling me.
     Do you put it down with the water on the floor, and will the water
    still rise if it is part of the drying process????  Please find
    out what you can and let me know.  I would greatly appreciate that.
         Thanks for all the information that I have received from
    everyone.
                                            s.f. (kathy)

    Within reason, the slower concrete dries out the stronger it is.
    Concrete is sometimes deliberately kept moist for as long as a
    month so it will be stronger.  Don't worry about the moisture;
    I'd guess it's "normal", and as a side benefit it's letting the
    concrete cure more slowly and making it stronger.  I'd wait a month
    or so and then put on a coat of masonary sealer (Thompson's Water
    Seal or similar).  You could then give the floor a coat of paint,
    if you wanted to hold down the dust even more.
    
    Note that concete doesn't harden by drying, anyway.  The hardening
    of concrete is a chemical process.

	I'd be real leary of sealing concrete before it has had a chance
	to dry and cure.  When I built a concrete bridge for my road over
	my brook, I had to keep a wet burlap tarp over it for several weeks
	to keep it from drying out too fast and weekening the concrete.

	The water in the concrete has to go somewhere.  If you seal it
	where does the water go?  Just let it dry and don't worry about it.

	-gary

    Just seconding (thirding?) the "let it dry of its own accord and
    as slowly as possible" motion.
    
    -joet

    Ok, thanks for all the info.  I was down stairs yesterday 20 May
    putting up the last of the insulation between the marriage walls
    and there was not as much water as there had been.  After reading
    all of these notes and seeing that I was truly releived.  In about
    a month I will put down the sealer though.  Thanks once again, I
    do feel alot better now.
         Have a GREAT weekend.
                                             s.f.

    I want to paint my garage floor and I'm looking for guidance
    on how to prepare the floor and what type of paint is best
    to use. Has anyone had any expierience with doing this and
    any recomendations to share?
    
    Dave
    

    Yo!
    
    Wash and seal the concrete with sealer such as Thopmson's sealer.
    then pain with a good grade paint tha's light; ie light green, grey,
    etc. dark colours will hide things that you drop.
    
    Sweep floors with kitty litter as a dust/oil binder when ever you
    change oil, work on car, etc. that routine will keep your floor
    painted for a few years. The fellow that owned our house painted
    the floor a dark green and I am forever trying to look for that
    washer or nut that I dropped.
    
    Hope this helps
    
    /cal

    There was an article in "Consumer Reports" a while ago about concrete
    paints.  They bottom line was to a concrete paint the required the
    floor to be clean and prepared prior to painting.  By preparing,
    the article meant washed with an acid.
    
    Also there was some mention of painted concrete being slippery when
    wet and ways of preventing accidents.
    
    

    It is a good idea to etch the floor with muratic acid before painting.
    If you dont it will look like aboulute he%% after about 6 weeks
    on a smooth surface. Broom treated concrete will hold longer.
    My parents tryed painting their patio without etching and now
    have a deck with a nice patio under it with a BAD paint job.
    
    You also want to be careful to wash away all traces of the acid.
    
    -j
    

    re: .-1
    
    "Etch the floor with muratic acid before painting."
    
    Could you please explain what you mean by "etch"?  Does this mean
    washing the floor with muratic acid? or some other more elaborate
    process?
    
    Thanx

    
    
    	Pour acid onto floor and then use push broom to scrub it. Muriatic
    acid does not require much elbow grease as it is very strong. I
    use acid staight out of the bottle for my swimming pool to raise
    the P.H. level. If you are going to do some etching with it you
    should wear a mask. The first time I smelled it I went down on my
    knees from the fumes ! When it comes in contact with the cement
    it will start fizzing and smoking. When we had the gypsy moth attack
    I had black ink or something on my concrete from them dying and
    nothing would get the stains out. Someone told me about the acid
    and it took about 2 seconds for the stains to lift off.
    
    Once again, be very carefull of the fumes, this stuff is very strong
    and powerfull.
    
    	-Steve-
    

I wish I could remember which type of acid muriatic is, but I seem to recall
either hydrochloric, hydroflouric or sulfuric.  In any event this is indeed
strong stuff.  As for the fumes, this is acid itself.  If you inhale it, it
will combine directly with the moisture in your lungs!

Furthermore, if for some reason you want to dilute it, NEVER add water to 
a container of acid or it will immediately start to boil and possibly splash
on you!  As they say, "when in doubt do what you oughta, add the acid to the
wawta" (must have been a Bostonian who wrote that jingle)...

-mark

    It's hydrochloric acid.  For washing down a garage floor you could
    probably dilute it.  Actually, I'm not sure you'd even need to use
    acid on it.  Just wash it down with water to get the dust off, put
    on a coat of sealer (Thompson's Water Seal or similar) and paint
    it.   My father painted his cellar floor and walls years ago, and
    he didn't do any fancy preparation.  30 or so years later the paint
    is somewhat worn but still in good shape.

    re .3
    
    Will muriatic acid remove the paint my big darlings dripped on
    the concrete front porch when they painted their bikes?  When I
    wash the acid away, will it kill the adjacent grass?

Here's what I did...  I went to Spags and bought a couple gallons of the Moore 
Industrial Floor Paint.  I got the light grey.  I think it's an epoxy base, 
but it doesn't require any catalyst.  They (Moore) reccommend etching first 
for new concrete (ours was <6mos old) so I did that first.  You thin out the 
first coat, and the concrete really sucks it up.  I did two more finish coats 
and it's really super.  I've spilled every kind of solvent imaginable on it 
including acetone and MEK, and they don't touch it.  I used a roller on the 
end of a broom handle and it went really quickly.  

The result was great, and I think the materials cost me about $50 including 
the Acid and the special thinner.  Don't even consider cleaning the rollers, 
buy cheap ones (medium nap) and just chuck them when you're done.


			Andy Ostrom

    re.4 the etching is simular to sanding a surface before painting.
    In the case of "soap finish"(glass smooth) it slightly roughs up
    the surface to help the paint hold.
    
    re.8 it will remove the paint provided you have already removed
    as much as possible with thinner. The action is not on the paint
    but on the concrete and removes part of the surface.
    
    The patio I refer to was 15 years old when painted the first time
    and the paint did say it was unneccessary to etch except on "new"
    concrete. The lable was VERY wrong the paint would flake off by
    someone turning around too fast. In other cases where etching
    had been done the paint still holds fast.
    I Strongly urge you to take the time to etch or i can almost
    assure you the paint will flake off long before it needs to.
    
    One other benefit is oil spots that might be on the floor will
    be removed at the same time. Oil will really cause bonding problems.
    
    -j
    

    Thanks for all the response. I have bought a couple of gallons of
    muriatic acid to etch the floor and enamel floor and deck paint.
    I will start this weekend and will let everyone know how I make
    out. I had one other question. I'm concerned with a slippery floor
    and since this is a work shop and I'll be working with power tools,
    safety is important. Has anyuone tried those additives (granular)
    that you add to the paint to get a non slip surface? Seems like
    the way to go but I'm not sure how effective the are. Any ideas?
    
    dave
    

    I already did a dir/keyword=(etc.) so please don't flame on me
    too bad if this has been covered.  I am going to be doing a
    30' X 24' foot concrete garage floor and have a few questions;
    
    Should the floor have expansion joints since it is so large?
    (the garage won't be heated) or can it be poured in one piece?
    How do you do the initial screeding (sp?) on such a large piece?
    (I'll finish it with a power trowler)
    Should the floor have stress relief seams if it's one piece?
    (A basement floor doesn't have these, but then it's heated too)
    Any comments on reinforcing besides the usual screening, etc. 
    
    Thanx
    Brian

>    I already did a dir/keyword=(etc.) so please don't flame on me
>    too bad if this has been covered.  

I don't think your question has been covered already anyway, but next time try 
note 1111.  It's much faster than doing the dir yourself.

Paul

    
    
    	The floor can and should be poured in one piece, that is no
    	joints.  It looks much better that way and you will usually
    	get cracks near cold joints between pours.   If you have 
    	properly poured a frost wall you should not get any frost
    	heaves or cracks.
    	You screat the floor with a bull float with a long extenstion
    	arm, also you can use a 2x6 to do an initial screat.  Make
    	sure you should elevations and mark the heights on the walls
    	so as to get a fairly even floor.  You may want to slope the
    	floor slightly towads the garage doors.
    	I would pour a 4" to 5" slab and reinforce it with either
    	wire mesh or 3/8" rebar.  This will also minimize the chances
    	for floor cracking.  
    	Start early in the morining, and schedule the cement trucks
    	@45 minutes apart.  Be sure that this should take you between
    	12 and 18 hours depending on the weather and how meticulous
    	you want to be about your finish slab.
    
    	Tony Grise.

    The easiest way to do the initial screeding is to section the slab
    off using pipes to keep the grade level.
    
                  _________________________________
                 |         -            -          |
                 |         ||           ||         |
                 |         ||           ||         |
                 |         ||<--pipes-->||         |
                 |         ||           ||         |
                 |         ||           ||         |
    
    You put the pipes in level using wooden stakes with a v cut in the
    top. Pour the slab a section at a time and after the screeding,
    remove the pipes and stakes.
    
    If you are pouring alone, you might want to put polyethylene on
    the gound. It will prevent the cement from setting up too fast and
    later will help to keep moister out.
    

    For a job that size have lots of help. My parents garage is 30 x30'
    and we poured it as one monolithic slab which as stated earlier
    is the best way to go. We had 5 helpers and could have used a few
    more. Remember they charge big $$$ if you take too long to unload
    and its not too hard to have it get away from you. Once it starts
    to set you better be ready to start finishing it off cuz it aint
    gonna wait. We used rebar around the side of the slab and remesh
    in the middle. 
    
    
    -j
    

    re .2 "you may want to slope ... towards the garage door": if this
    is Mass, you are required to have a 4% grade.  it does not have
    to be uniform - you can have more of the grade at the entrance to
    the garage door than you do at the back of the garage, but the grade
    from front to back is required.
    
    (4% = 4" vertical drop per 100" horizontal run).
    -reed
    

    RE: .5
    
    And what if it's not?  I have a fairly new house and sometimes water
    will go under the garage door from outside and sit in the middle
    of the slab.  Is the builder responsible for this?
    
    -al

I sloped mine 2" in 24'.  I was going to go 4" but my floor finishers
didn't think that would be too much.  The 2" seems to be good.

They also put an angle iron where the door meets the concrete.
Try for picture:      .
                      .
                     | | door
                     | |
                     ---
                    /   \    weather strip
            -----   --+
         gar floor    |---------------+
                           apron      |
      --------------------------------+
                   \
                    \
                      ----slab

As the door comes down the strip forms a nice seal and the water flows
out of the garage but not in.  The bottom panel of the door cathes hell
from water splashing up so I also built an overhang of about 2' over the
door.  While my neighbors are all replacing their bottom panels every 3
or 4 years, I sleep nice and sound.

I had also heard the the slope is somewhat a safety feature.  Supposedly
gas and fumes 'hug' the ground, and do not dissipate into the air.  If the
garage is sloped towards the doors, the gases will flow out of the garage,
not into the other end. 

I can practically guarantee that something is wrong with your definition of the 
4% slope necessary in a garage.  By the figuring of 4" per 100", a typical 24 
foot deep garage (288 inches) would slope nearly a foot.  Neither in Mass nor 
anywhere else have I ever seen a garage slope like that.

1-2" per 10' sounds much more reasonable.

Paul

    I have a dumb question:
    So what if the slab cracks? My father had a garage floor poured
    about 20 years ago, and now it has a few hairline cracks, at least
    one all the way across. Doesn't affect it any, though. Plus, it's not
    like it's gonna rain in the garage and then freeze. -Tom R.

This is one of those things where just because it's possible doesn't 
mean it's a good idea, but:

You have to have the kind of floor that's been finished ultra-smooth.  
About as smooth a quarry tile.  Then you use a paste that comes in a can 
marked "TREWAX"  I don't know if that's the maker or the brand name.  
You apply it like any other paste floor wax, and then buff with one of 
those electric buffing machines. (Most rental places have them if you 
don't own one.)  What you end up with is a floor as trecherous as 
freshly waxed tile and as hard as cement.  Great combo.

					>>>==>PStJTT

    I don't know about the wax - I wouldn't do it.
    
    The crew that did my garage floor did a super job.  I then kept
    it wet for a week, to let it cure real good.  I then let it dry
    for a week.  I then sprayed on Thompson's water seal.  Actually
    I don't think it was Thompson's.  It was a concrete sealer from
    Corriveau Routhier.  about $45 for five gallons.
    
    However, I have since spilled oil and what not on the floor and
    it comes right off slicker 'en ...
    
    Highly recommend the sealer.  No on the wax.

    I suspect that you have to start with the right kind of concrete,
    as mentioned in .1.  There's a finishing technique for concrete
    that results in a very hard, smooth surface, much smoother than
    what you get with "normal" troweling.  Where I went to college,
    they had that kind of floor backstage at the theater.  I can
    imagine polishing that with wax and getting something that looked
    more or less like one gigantic piece of gray tile.  However, I
    don't think you'd get much if you tried polishing concrete that
    has the kind of surface you almost certainly have on the concrete
    in your house.

    re:2
    
    I have an old concrete stair entrance. It is still in pretty good
    shape, no chipping nor cracking. Would Thompson work on old concrete
    ? do I need to prepare the surface before applying it ? Will it
    become slippery afterword ? And how many coats should it be applied?

    I second the sealer. I suppose you could wax the sealer afterwards
    if you really wanted to....
    
    -j
    

    re: .5
    If you have that kind of floor, you did well.  Personally I've never
    seen one in a house, but that certainly doesn't mean there aren't
    any.  And they sure are nice!

    Would the use of the Thompsons water seal reduce the concete dust
    that I have in my basement...The dust gets thick when the kids are
    buzzing around on their skate boards?
    
    Bob
    

    
    
    		ABSotutely!!
    
    Just make sure you do a good job cleaning with a shop vac prior
    to sealing.  I think I'd recommend at least 2 coats.

    re .8
    
    Its also worth noting that that dust is particularly irritating
    to respiratory tissue because cement is alkaline.
    
    -Bob
    

    
    I used a sealer on my cellar and garage floors and it definately
    makes a difference.  There is virtually no dust, etc.  I purchased
    the sealer from Kesseli and Morse Co. in Worcester.  Can't recall
    exactly what it cost, but it's worth the money.
    
    However, I have one problem.  A month or so after it was sealed,
    my friends little boy spilled a soda on the floor.  It wasn't noticed
    for while later, this was during new construction.  It is very sticky
    now.  Does anybody have any ideas how to get this sticky soda off
    the floor??

	re: .-1
	
	How about using  muriatic  acid to etch the surface followed bt a
	thorough washing with soda to neutralize the acid?
	
	Chris

    RE: -.1, muriatic acid.  Can you be a little more specfic on how
    to do this?  Spray it on?  Brush it on?  Let it set for how long?,
    etc.

	You pour it on the floor and  swab  it  around  with a disposable
	mop.  Because concrete is alkali, it will  neutralize the acid on
	is  own, so adding more acid as its action  slows  down  will  be
	necessary to roughen up the surface.  All you want  is  to create
	enough of a rough surface to allow the glue to hold  the flooring
	down.    How  much  time  that'll  take  is  unknown.   As far as
	suppliers, I'd  try  a well stocked hardware store, not someplace
	like Grossmans, NHD  or the like.  This is specialty stuff and if
	it dosen't move thru a store, it generally dosen't get stocked.
	
	I've used it to  prepare a floor  prior  to painting and it works
	well.    The  paint  is  still  down    (10    years)    with  no
	flaking/chipping, etc.
	
	Chris

Yow!  Swabbing a whole floor with Muriatic?  We're talking SERIOUS ventilation 
here.  The fumes from that stuff are POTENT.

Paul

    You can get muriatic acid at Wickes in Acton.

    I'm seriously considering this approach, and will open all windows
    and have fans blowing.  Just how potent is the stuff?
    
    I've never used muriatic acid before.  Is it a liquid, or a powder to
    be mixed?  Do I dilute it?  Do I have to let it set a while? And, how
    do I know when I've sufficiently neutralized it (with baking soda?)
    after I'm done?    Obviously, I'll try a small section first, so I
    don't accidently create a sub-basement, but the more I know ahead of
    time, the better my chance of success.  I wouldn't want all of you to
    read about me in the papers. 

    Just for reference:
    
    	muriatic acid = hydrochloric acid 
    

>        I'm seriously considering this approach, and will open all windows
>    and have fans blowing.  Just how potent is the stuff?

    I've used Muriatic acid many times to clean rust off of metal. Even
    outside the smell is bad.
    I can't imagine being in a room where you've covered the floor with
    it!  Good luck.
    
>        I've never used muriatic acid before.  Is it a liquid, or a powder to
>    be mixed?  Do I dilute it?  Do I have to let it set a while? And, how
>    do I know when I've sufficiently neutralized it (with baking soda?)
>    after I'm done?    
    
    It's a liquid.  I don't know if you need to dilute it for your
    application but probably not.  
    
    Make sure you get it all mopped up when you're done. 
    Otherwise, you'd have The China Syndrome.
    

    I used it to prepare a terne metal roof for priming and with some
    sensible precautions did not have any incidents.  Yes the fumes
    will irritate eyes and nasal passages.  So you definitely want to
    ventilate.  I found that with a breeze outside I just stayed upwind.
    If I were to do my basement I would wear googles and my respirator.
    You would do well to have a water source nearby in case of accidental
    spill in your eyes or on your skin.  It will burn if you leave it
    on, but we're not talking burn through your pants and leg as you
    stand there.  If you wear rubber gloves and rubber boots and don't
    slop the stuff around you'll do fine.  A few box fans to set up
    good cross ventilation would be real helpful or you'll find yourself
    running out for a breath and then running back in to keep working.
    That happened to me a few times on the roof when the wind shifted.
    
    re: -1  Muriatic acid is dilute Hydrocloric acid and cement is alkaline
    so they will nutralize themselves before you do much more than etch
    the floor.  
    
    You can expect to throw the mop away when you're done.  It ate up
    the rags I used to clean up with. 
    
    But so long as you coverup with whatever rubber or neoprene garments
    you have, protect your eyes and respiratory system and keep a ready
    supply of water on hand to dilute any accidents you will have taken
    all reasonable precautions.
    
    -Bob

    Muriatic acid is commonly used to clean in-ground Gunnite swimming
    pools.  Even outdoors in a swimming pool, use of a respirator is
    recommended, and it's still an unpleasant job at that.  Also, it tends
    to eat away enough of the Gunnite finish to make the surface feel
    rough.  Pools which are cleaned in this way each season require
    resurfacing every few years.
    
    In short, I would NOT recommend this for internal (ie, inside the
    house) use.

    hmm.  Come to think of it, when I did my roof I had some tools that
    I'm sure I didn't spill any acid on, they must have just been down
    wind and they were all rusted within a few days.  I wonder what
    the fumes would do to things like your water heater, furnace, gas
    pipes, ductwork and what not.  I would like to retract the enthusiasm
    I expressed for this idea back in reply 22.
    
    What was your reason for not just renting a floor sander with the
    most abrasive paper they'll sell you and seeing what happens?
    
    -Bob

    
    Why not try TSP (Tri Sodium Phosphate)?  Same idea as HCL,
    but it's alkalai instead of acid.  Fumes are not so bad, but
    wear good chemical-proof gloves.  You can buy it in any hardware
    store as a powder, and mix up a strong solution.
    

    The gas created is clorine(or so I was told) which is to say the
    least deadly. Anyone know otherwise?
    
    -j

    Muriatic acid (ie hydrochloric acid) is made by dissolving hydrogen
    chloride gas (HCL) in water.  What you smell is really the HCL gas
    being released from solution.  When the acide reacts with with
    concrete, it is really reacting with the limestone which is calcium
    carbonate.  The products of that reaction is calcium chloride (a
    salt) and water:
    
           HCL + CaCO3 = H20 + CaCl (forgot how to balance equations!)
    
    HCL gas is not quite as bad as Chlorine, but it still requires all
    of the safety precautions talked about.  BTW, muriatic acid is commonly
    used indoors to clean brick fireplaces.
    
    Bob
    

    re: .24, renting a floor sander.
    
    As soon as I mentioned it was for concrete, the rental places refused
    to rent one to me.  Reasons ranged from "it will tear the belts
    apart too fast" to "concrete dust will kill the motor".  Whatever
    the reason, I'm not anxious to kill the sander, or to create all
    that dust if there's a better way.
    
    RE: .25, TSP.  Will TSP etch the floor?  I've heard of using it
    as a cleaner, but didn't know how if it would do more than remove
    dirt.  If I use the acid, would a wash with TSP after be a good
    idea to make sure the acid is neutralized?
    
    RE: fumes.  This isn't a "basement" in the traditional sense.  It's
    the lower level of a split entry, with lots of full-size windows
    and a sliding glass door at the back of the room.  I can keep a
    pretty good breeze blowing thru at all times.  I'm going to pick
    up some muriatic acid and try a small area first.
    
    RE: respirator.  Are we talking air tanks, or a type of "gas mask"
    with filters?  [not the paper surgical masks, but something designed
    to filter out toxic fumes]
    
    Thanks for all the suggestions so far.  I'll let you know how it
    works out.  I'm going to try it Saturday if all goes well.
    
    -db

    I doubt that TSP would etch the floor; I expect you need the acid
    for that.  
    With good ventilation (fans, etc.) and working in a small area at
    a time, I expect you could use the acid.  Give it a try; if the 
    fumes are too bad you can always stop.  You could try diluting
    it, too, to make it a bit less fierce (from basic chemistry again:
    "Add the acid to the water, not the water to the acid").  

>    (from basic chemistry again:
>        "Add the acid to the water, not the water to the acid").  

    All right, I don't get it. How basic was this chemistry?  Maybe
    what I took was too advanced.
    

    Re .30:
    
    If you want to dilute acid, DO put some water in a bucket, and then
    add the acid; DON'T put the acid in a bucket, and then add water.
    
    stephen

    re last couple
    
    If you add acid to water it immediately begins to become a dilute
    solution.  If any gases are given off the rate of reaction very
    quickly (exponentially) decreases.
    
    If you add acid to water,  The rate of reaction remains vigorous
    until all the water is exhausted.  (almost true)  If there are gases
    being given of chances are that the acid vapor will be carried off
    in an explosion like reaction.  The pourer is standing in the way
    of this of course.  This is a strong solution that the pourer gets
    splashed with.
    
    In the right way if there is any acidic vapor caught by the pourer
    it is likely to be very weak by the time it reaches him/her.

    RE .32
    
    Could you run that by again ???

>                                   -< Say Again... >-

>    RE .32
    
>    Could you run that by again ???

    I understood it.  But I assumed that there's a typo in the first
    sentence of the 2nd paragraph.
    

    Right.  Second paragraph should read "If you add water to acid..."
    
    If you add acid to water, looking at it in slow motion we see an
    acid molecule surrounded by many water molecules.  Dilutes very
    quickly.
    
    As we pour water to the acid, looking again in slow motion just
    below the surface of the acid, we see a water molecule surrounded
    by several acid molecules.  Very vigorous, violent reaction (boils).
    
    Did I get it right that time ??

    I've looked through the file for the answer to my question. It
    may fall into many notes but doesn't fit exactly so I thought
    I would start a new one.
    
    I want to paint a breezeway floor. It's poored concrete and was
    painted many ( <30 ) years ago. The paint is adhering fine, I
    just hate the color.
    
    I want to know if I will have to etch the floor with muratic acid.
    The descriptions sound awful and I'd like to stay away from it
    if I could.
    
    I am going to try to find out what kind of paint is already on
    the floor. I read in this file about rubbing alcohol (if paint
    comes off it's latex) and check if a paint chip stretches (latex)
    or if it cracks (oil). If I can't find out what kind of paint
    it is I'll put an oil based primer down then paint with latex.
    I'd prefer to paint with latex paint. I did read about paint for
    concrete. Do I need a special kind of paint also?
    
    Thanks for any advice
    Linda
    
    

    
    	There are special paints made for this purpose.  Most of them
    go under some kind of "Floor and Deck" name.  They come in latex
    and oil, and are made to endure walking, etc.  I really don't think
    you need to go to all the trouble of Muriatic acid for painting.
    If you do, you'll have to make doubly sure you get rid of all the
    acid residue before you paint.  Best bet is to go to a good hard-
    ware store or paint supplier and get their expert advise.
    

I just got off the phone with Tony Coutreau talking to him about doing my
cellar floor.  He sounds like a good man, but that's a discussion for the
contractors note.

I put in a drain pipe and covered it with crushed stone to help reduce moisture.
I was also planning on covering it with 6 mil poly before pouring the concrete.
Tony said if I do that it'll cost me more for him since it will take much longer
for the concrete to dry (nowhere for the water to drain).  He then went on to 
say that it's my money and I can spend it any way I want, BUT -- he felt the 
plastic would rot out in around 5-7 years anyways and therefore why bother at 
all!

Opinions?

btw - 	for anyone interested in how much a floor costs, he said he gets about
	$25/yard providing there is reasonable access for pouring.  concrete
	runs around another $50-$60/yard.

	almost forgot - he asked me where I got his name and when I mentioned
	digital he laughed...  seems one of us is his neighbor and has been
	showing him some of the correspondences

-mark

    	There are a variety of polymer films that will do the trick,
    AND last for many years.  Plastic does not rot in a classical sense
    but instead breaks down in sunlight, or has the plasticisors leach
    out causing brittleness.  I think I'd try calling DuPont consumer
    division for more information and to see what is available.
    	The reason he charges more is that it will take longer for the
    concrete to cure.  Concrete does not dry but instead uses the water
    in a chemical reaction to harden the material.  Usually the concrete
    company would cover the cellar floor after pouring with a plastic
    sheet to prevent the concrete from drying rapidly.  The slower the 
    concrete cures, the harder the concrete.  I remember reading that
    concrete takes up to 8 years to fully cure.
    	I think the plastic sheet is a good idea.  Maybe someone with
    a more up to date polymers background can recommend a material. 
    I'm not sure I buy his assertion that polyethelene sheet would last
    only 6 years.  I hope not, since that's what I use for a vapor barrier.
    
    					=Ralph=

>    	almost forgot - he asked me where I got his name and when I mentioned
>	digital he laughed...  seems one of us is his neighbor and has been
>	showing him some of the correspondences

    I confess.

    
    	If you think you have a water or moisture problem (putting in
    a drain pipe would indicate that), put down the poly.  I did on
    mine and I'm glad I did.  The cost for my poly, Calcium Chloride,
    and labor to put it in was an extra $75.  I'm not an expert on 
    plastics but I disagree that the poly will disintergrate in 6-7
    years.  If it does, then I'm in deep trouble because my poly-vinyl
    clorate drain pipe is also buried beneath the floor.  Won't happen.
    	The Calcium Chloride is what helps absorb the excess moisture
    caused by the plastic.  And yea, it takes a little longer to dry,
    but my contractor was in and out of there in less than a day, and
    the next morning I could walk on the surface and bring all my junk
    back into the cellar.
    	No offense to VIDEO::FINGERHUT or his neighbor, but you should
    also get a couple other contractor bids and opinions.

    If he's relying on excess water draining out of the concrete, he's
    getting it mixed with MUCH too much water!  As mentioned, concrete
    doesn't harden by drying out, it hardens by a chemical reaction,
    and you get the strongest concrete when you have just enough water
    to do the chemical reaction with none left over.  Naturally in the
    real world you can't hit the mixture that accurately so you always
    mix with a little excess water, which also makes the concrete more
    workable, but it's best not to overdo it.  
    There is a certain amount of drying that goes on, but as also
    mentioned, the concrete is strongest when that occurs slowly.
    As far as the quality of the concrete is concerned, the vapor
    barrier under it is probably A Good Thing.  Based on my limited
    experience talking with contractors, it seems that very few of 
    them have more than the haziest idea about how concrete really
    works.
    
    In Strength of Materials engineering class, we did strength
    tests on concrete test cylinders mixed with different amounts of
    water and cured in humid conditions for varying lengths of time.
    The samples mixed with lesser amounts of water and cured for 28
    days were truly impressive when they finally shattered under load!

    Even you don't have an excess of water in the mix for the pour, there
    is still going to be tons of water to dissipate. The solution for 
    your man to get home a lot earlier and for you to save some money 
    is to put the poly down BUT just cut slits in it to give the water 
    a way out.
    
    1/8 slits are not going let a lot of moisture back up through the 
    concrete later on. I learned this through a Canadian contractor a 
    few years ago. It works!

    
    Steve

	Steelcote (314 771 8053) describes their Water-Out thus:

	  Protects concrete surfaces from moisture penetration...

	  Protects concrete against carbon crusting from automobile
	  exhaust fumes and acid rain.

	  Makes walkways, steps, and ramps less slippery as concrete
	  does not wet with rain.  This would also apply to bridge
	  decks and highway curves.  [Now _this_ is useful! rd]

	  Inhibits freeze/thaw spalling.

	  Protects against salt efflorescence and lime erosion.

	  No gloss formation...

	  Proper application may be ascertained after overnight dry.
	  Sprinkle impregnated surface with ... water.  Area should
	  "bead" ... and not "wet out" and darken.

	  etc. etc. etc.

	They sell 1 & 5 gallon pails (55 gal special order.)

	I've never used this stuff, but their claims are sure
	impressive.

	Regards, Robert.

Another alternative to floor sanders would be a small floor polisher with
wire wheels. (the kind of polisher with two ~6"d buffer wheels)... or maybe
grinder wheels...

JMB

    
      I just removed a tile floor that was over concrete in our
    basement.  The floor was 20 years old and tiles had been lifting
    the past 5 years or so, from water coming in during the spring
    (not that much, but enough to lift the tiles after a while).
    
      The tile was adhered using tar, most of which came up with the
    tiles or had worn off where the tile had been off for some time.
    My question is "how do I get the remaining tar off the concrete?"
    
      I've tried sanding, roto-stripping, putty knife, but doesn't
    get it all.  When I get it all off, I will use muriatic acid, then
    water seal and finally paint it.   As there is the potential for
    some water in the spring, I will probably use scatter rugs over
    the painted floor.
    
                           Mark
    

    A solvent like paint thinner or kerosene should attack tar.  
    
    Bob

    Re .41
    
    Muriatic acid should smell like a semiconductor wafer proceessing
    facility, since it's just diluted hydrochloric acid, which is used
    in wafer etching.  The fumes are chlorine; not only poisonous, but
    explosive in the proper concentration.  Only use the stuff outdoors
    when everything else has failed.
    
    pbm
    

    Well I painted the floor and it turned out to be a disaster. I
    found and epoxy based latex paint made by Benjamin Moore Paints.
    I roughly sanded the floor with a belt sander and meduim grit sand
    paper. I vaccummed and washed the floor. I put down 2 coats of
    paint that doesn't stick.
    
    I noticed that it wasn't sticking when I put down masking tape and
    pulling up the tape removed most of the paint. A lawn chair made
    lots of scratches in a little amount of time. I let it dry for 3
    weeks just to be sure, we have had some terrible weather in New
    England.
    
    A representative from Benjamin Moore came out to look at the floor.
    He confirmed that I did everything right. It's just my bad luck
    that it is not sticking. So now I have to remove the paint before
    carpet or linoluem can be put down. I rented a belt sander, it
    is a very slow process.

    While looking at paint removers somebody told me that the pain that
    was already on the floor may be a sealer and if it is, nothing will
    stick to it.

    I'll never paint a concrete floor again :-(

    

    
    Re:  .2
    
    I'm really sorry to hear about that.  You obviously used the wrong
    kind of paint.  My parents painted their basement floor with an
    epoxy paint (not a latex!), and it's great.  It's held up for
    years (~10) and is easy to clean.  I believe that the only preparation
    they did was washing the floor with TSP.
    
    -tm
    

    Well it isn't guaranteed no matter what you use.  Some cured concrete
    exhibits a phenomenon called "chalking", which means that the surface
    is continually breaking down into dust-sized particles. I'm not
    sure as to what causes this, i.e., improper mix/materials, improper
    curing conditions, or environmental factors, but it does happen
    and such a surface will be nigh on impossible to hold anything short
    of lag screws.  
    
    Jim
    (who on one job had PL400 construction adhesive literally fall off concrete
    like this after a couple of months )

    
    I was suprised to hear about the Moore paint.  On my new house with
    the foundation suitably aged, over six months, the Moore epoxy latex
    went down easy and is holding well.  My wife had her doubts at first,
    but the decrease in dust and the ease of cleaning, means I'll never
    get by with bare concrete again.  Now, however, I'll have some
    reservations about promoting the concept to everybody I meet.  I
    really never heard of concrete that couldn't be treated to hold
    paint.  Live and learn.
    

    I would like to paint the concrete floor of my basement to control
    chalking, ease cleaning, and hopefully, to cover some urine stains
    from my dogs.  As was mentioned in another note, once the scent
    is there, they return again and again.
    
    Two questions:
    
    1) Aside from cleaning the floor with one of
    {Odor Disposer | white vinegar | oil of Bergamat (sp?)}, do I need
    to clean with anything else or use some sort of sealant prior to
    painting?
    
    2) Will the cleaning/[sealing]/painting seal the odor sufficiently
    to prevent the dogs from detecting it?
    

    If you want a nice surface that's easy to clean, why not put down
    vinyl tiles?  They're not too expensive and definately a DYI job.
    I painted the cement floor and several years later decided to tile.
    It wasn't fun getting the paint off before laying the tile.  The 
    tiles might seal the doggy smell in better.  

    I have a question and could use some help.  This topic seemed as
    good a place as any to ask.
    
    I want to finish off a bathroom in the basement.  It was rough plumbed,
    so there is a waste pipe coming through the floor which has a cap
    on it.  This is for the toilet.
    
    My problem is that this is in the wrong place.  I need to break
    open the concrete, move the waste drain, etc.  I don't think I will
    need to move it very far, probably less than a foot.
    
    How would you recommend that I tackle this?  If I start smashing
    concrete with a sledge, can I break open the PVC pipes that go through
    the concrete floor? 
    
    /Jim Pappas  

    You drill a series of holes in a line where you want the pipe to
    move to on both sides of the 'channel'.  Take a cold chisel and
    break up the ridges left and you have a cut in the concrete that's
    where you want it.
    
    Of course, the best way is to rent a diamond wet saw if you can
    find one.  Don't use a concrete blade in a skil saw.  You'll not
    get through and will have ruined your skilsaw.  This latter is a
    lot cleaner but it don't come cheap.

    Another dumb question (at least it's dumb to be asking it at this late
    stage in the game):
    
    Is the slab for the garage floor positioned on top of the front
    foundation, or strictly inside it?  Putting it on top means the
    foundation will help hold up the slab, but it also means a short steep
    rise into the garage from the driveway (good for drainage, bad for
    driving into the garage).  Putting it inside will maintain the current
    driveway grade, but means will probably always have a crack between the
    floor and the foundation.
    
    How carefully must the ground be graded before pouring?  Must it match
    the final slope of the floor, so that the slab has a uniform thickness,
    or is the pourer's job to insure the slope, regardless, so that the
    slab might be thicker in the back than in the front?  Do all the little
    holes where small rocks have been removed need to be filled in?  Given
    that we're mostly removing stuff (all the organic matter must be
    removed), and will be adding very little, is a final compaction run
    necessary?
    
       Gary

    Help!  We have white, cottony mold/mildew growing on our concrete
    basement floor.  It is concentrated around our fuel oil furnace.
     We have already tried two applications of bleach to kill it, but
    it's resilient.  Any suggestions?    
    
    
    Ken and Joan (new old home owners)

     Try TSP a well known mold/mildew killer and remover. It can be
    found at most hardware stores. TSP stands for TRI SODIUM PHOSPHATE
    I believe.

    TSP is also the main ingredient in SPIC & SPAN according to others
    in this conference.  

    Re .1, .2
    
    TSP is also the main ingredient in powdered dishwashing detergents.
    
    pbm
    

	Help! I'm so confused!   I've read all the concrete floor painting
	notes (226.*, 1983.*, 2181.*, 2864.*).

	I've just moved into a 3 year old "one-car over" style townhouse.
	I want to paint/seal the concrete garage floor, and also the 
	concrete floor of the utility room.

	If I use Thompson's Water Seal (followed by "regular" paint) 
	I don't have to etch with muriatic acid first?  (But maybe clean
	with TSP?)

	If I wash with TSP, how long should I let the floor dry? 
	Overnight, I guess, but is that enough (1 day) ?

	If I use epoxy paint, like Moore's Industrial Floor Paint, I 
	gather I need to etch first.  But I REALLY don't want to mess
	with acid, especially in the small (18'x6') laundry/furnace room
	in back.  I want to make a small workshop there, but there's no
	ventilation to speak of, and besides, I've read its not a good
	idea to use acid around one'e furnace/hot water heater.

	So that leaves Thompson's & regular paint?


		Josh

     Peter Hotton (SP?) the Boston Globe's handyman has responded several
    times to this question. He says if it's not painted, then dont.
    Apparently paint on concrete just doesnt adhere well. Although there is
    a "dye" for wet concrete , to color it prior to setting it in place.
    
    P. Hottons opinion is put here without permission, and I am
    paraphrasing.

    
    Re: .12 and .13
    
    Two part epoxy paint is great on the concrete I've seen.  My parents
    did it about 15 years ago, and it still looks perfect.  My suggestion
    is wash the floor and weight until it's thoroughly dry (at least a day
    or two) and use some sort of clear sealer. If you're happy with it then
    fine, if not, then you can consider the paint option.  Yes, you
    are right about the etching being unpleasant in a poorly ventilated
    area.  I wouldn't worry too much about the furnace or hot water
    heater, unless they are sitting on the floor.  I would definitely
    not store muriatic acid in the basement, though, because metal objects
    could tend to rust faster with prolonged exposure.
    
    -tm
    

    We paint my mom's basement whenever she gets the whim with floor and
    deck paint.  We've had no problems with peeling, and I know my parents
    didn't do any fancy prep work besides sweeping.
    
    Elaine

	thanks for the previous replies, but no-one has given any info 
	on:

	If I use a sealer, such as Thompsons, or ULG Sealer (Somerville
	Lumber's), does that reduce the need to etch?

	that is, does sealer stick to un-prepped concrete better than
	oil paint (thinned for the first coat)?  I can deal with
	putting down a coat of sealer, and then a coat or 2 of paint.

	But I want to start sealing (or painting) tonight, since I had
	to move my washer & dryer out of the room - so can someone
	answer soon?

	I have washed the concrete walls and floor of my utility room
	with "Dirtex", and mop-rinsed (sucking up the dirty water with
	my neat-o water-sucking nozzle on my Shop-vac).

	I can deal with etching my _garage_, where I can flush the acid
	out with a garden hose.

	Has ANYBODY here ever etched concrete "_indoors_" ??
	(and managed to avoid looking like The Phantom of the Opera?)

	Thanks for the advice!

		Josh

    If anything, I would expect that using a sealer would make it more
    difficult to paint.  The idea of the sealer is to prevent things from
    being absorbed into the concrete.
    
    Why do you want to paint it?  There seems to be a pretty strong
    consensus that sealing is better.  We just took the advice of the
    person who poured our brand new garage floor and sealed it.  We have no
    intention of painting it.
    
       Gary

	Well, I'm probably guilty of wanting to discuss painting my
	_utility_room_ in the "Painting Garage Floors" note :-)
	Actually, I had a 2-part question, one about my garage floor,
	one about my utility room floor.  So here I is!

	I want to make my small utility room into a habitable space, I
	am going to build a 6'x32" electronics workbench into the end corner 
	of it.  I also have 2 steel-shelving units full of electronic 
	"junk" and small hardware, in this room.  Since the floor and rear 
	wall are bare concrete there its always dusty, and I definitely do 
	not get along with breathing alkaline concrete dust.  It gives me a 
	hard time breathing when the dust gets stirred up, as from sweeping 
	or vacuuming.  Since the washer and dryer are in this room, and I am 
	not a slob, I expect to be regulary sweeping or vacumming up the lint 
	that natually (no matter what) comes out of the dryer.  (it vents 
	correctly and works correctly, I guess its from when I take out and 
	clean the lint trap, some lint flys around).

	So I want to seal, or paint, the concrete to make the room more 
	livable.

	Likewise for the garage, I want to cut down on dust generation.

	BTW, the "how-to-use-UGL Products" (masonry sealer products) leaflet 
	I got at Somerville Lumber recommends their sealer as a "primer"
	for paint.  but one saleman said I only needed to use 2 coats of
	paint, thinning the first coat, a second salesman said "What does
	the label on the paint say? -'etch?'  You etch!"

	time to go back to Somerville and re-read them labels!

		Josh

My personal opinion is that bare concrete looks ok for a utility room or
work room floor, but that painted concrete, from which the paint has
peeled or been abraded off in places, looks downright ugly.  I have a
concrete floored porch that was painted at one time, and now is a bare
concrete floored porch along the main traffic path.  We plan to amend the
problem by tiling it.  For a work room, though, how about painting the
walls, to make the place brighter, and just sealing the floor?

As for the question of whether etching is needed on the walls, beats me.
But since walls get a lot less abrading than floors do, I would not think
that it would be necessary to be so fancy in the preparation.  I should
add that I am strongly biased against etching, simply from watching some
friends do it outside on concrete blocks.  They were gagging, even pouring
the stuff on at arm's length in open air.  All right, so I'm exaggerating
a bit, but it even smelled bad to me and I was 10' away.  So I personally
would avoid etching if at all possible.  People who aren't as sensitive to
nasty odors are welcome to a different viewpoint.

	Enjoy,
	Larry

    I used the UGL clear concrete sealer on my basement for the same
    reason you want to seal: to keep the dust down. I just swept the
    floor and put the stuff on with a roller... no etching or anything..
    still looks nice 4 years later. I think next time I clean the basement
    I'll toss another coat on the high-traffic areas, although you can't
    see any color difference where the traffic has been.
    
    It takes two coats to cover. The first coat gets pretty well soaked
    up by the concrete. Given the way the concrete soaks the stuff up,
    I have a hard time believing there would be an adhesion problem;
    maybe if there's soap/oil/etc on the floor you'd have to clean it
    up..
    
    ...tom

re -.1,

>    It takes two coats to cover. The first coat gets pretty well soaked
>    up by the concrete. Given the way the concrete soaks the stuff up,

	yup, thats what I've found.  Before putting on sealer, my floor
	was much smoother than the wall. So I've found one coat on the
	floor covered it pretty well.  After drying 24 hours it was still
	slightly sticky so I'm letting it dry till tonight...
	The wall however is very porous and really soaked up the first coat.
	The second coat (done last night) used up only about 1/4 as much
	sealer, tho the wall still isn't nearly as "smooth" as the floor.
	But at least its not so dustly anymore.

	Tonight - it all gets a coat of oil-based paint, then another coat
	tomorrow AM!

		Josh

    I have the same question as Gary had in the last reply. I don't
    see an answer so I will put in my question.
    
    Is the slope of the graded ground surface prior to pouring the
    the finished concrete floor the same as the floor? 
                                                       
    How should the floor be at the front of the garage? See my diagram
    below.
    
   
                                       This way?....
                                                    .
                                                     .     _____
                                                      .   |     |
                          Finished floor....           .  |     |  Apron..
                                           V            . |     |         V
    ---------------------------------------------------------------------
   |                                                       _____         |
    ------------------------------------------------------|     |--------
                                                          |     |
                                                          |     |     
                                                          |     |
                                       OR THIS WAY? .      -----
                                                     .     _____                
                                                      .   |     |
                                                       .  |     |
                                                        . |     |
    ----------------------------------------------------------------------
   |                                                                      |
    ----------------------------------------------------------------------
                                                          |     |
                                                          |     |
                                                          |     |
                                                          |     |
                                                           -----
                                                    

    I'll answer my own question, since we had the floor poured a couple of
    weeks ago (another outstanding job by Tony Cotreau).
    
    The floor rest on top of the footing at the front of the garage.  I
    suppose you could have an apron extending out beyond the front of the
    garage, as the picture in .12 seems to indicate, but we didn't.  We
    just used some long scrap lumber (at least 2 by 6) nailed to the front
    of the trim on the garage, and supported by lots of rocks and some
    extra bracing, to form the front edge of the slab.  If you want the
    apron to stick out, you'll have to build forms around the three sides
    that are exposed, and support the forms properly.  We're planning on
    putting in some drain tile, probably about a foot deep, and just
    filling right up to the edge of the garage.  Eventually we may get
    around to something better than a dirt driveway.
    
    Concrete is more expensive than dirt.  If you don't slope the grade,
    you'll either wind up with six, very expensive inches of concrete in
    the back, or two fragile inches of concrete in the front (assuming a
    two inch slope and a four inch slab).  It isn't necessary that the
    slope be perfect, but you'll have a thinner floor where the ground is
    too high, and you'll use extra concrete where the ground is too low.
    
    We wound up compacting the dirt, and it compacted more than we
    expected.  Therefore we had a mad rush to move more fill into the floor
    area before the concrete arrived.  Fortunately, Tony had ordered an
    extra yard for a project of his (since he's a neighbor), so we had
    plenty of concrete for our floor, but he barely had enough for his
    project.  Running out of concrete is a mega-disaster (well,
    kilo-disaster).
    
       Gary

Gary

Just got around to finishing this note looks like you beat me to it but
this may help someone else.


RE: Note 1476.11           New Garage Floor Help Requested              

>    Another dumb question (at least it's dumb to be asking it at this late
>    stage in the game):
>    
>    Is the slab for the garage floor positioned on top of the front
>   foundation, or strictly inside it?  Putting it on top means the

On top of the foundation is the standard way to put them in. I added
a new twist by installing a piece of 1x6 P.T. for a thermal break at the
garage door. (I was spending big bucks to have an insulated garage and 
foundation and could not see having a 16 ft cold conductor.

>    foundation will help hold up the slab, but it also means a short steep

I hope not if it does your floor will crack.

>    rise into the garage from the driveway (good for drainage, bad for
>    driving into the garage).  Putting it inside will maintain the current
>    driveway grade, but means will probably always have a crack between the
>    floor and the foundation.

Do you like frozen garage doors? Without a slope away from the door water
may (will) settle at the bottom of the door causing ice build up that will 
either freeze the door shut, allow a gap when closed or turn the door into 
a yo yo if you have a garage door opener.
4" inches is not to hard to make up in 2 or 3 feet. 

>    How carefully must the ground be graded before pouring?  Must it match
>    the final slope of the floor, so that the slab has a uniform thickness,
>    or is the pourer's job to insure the slope, regardless, so that the
>    slab might be thicker in the back than in the front?  
>    Do all the little
>    holes where small rocks have been removed need to be filled in?  Given
>    that we're mostly removing stuff (all the organic matter must be
>    removed), and will be adding very little, is a final compaction run
>    necessary?

Yes be as close to grade  -slab depth as possible. 
1 You will save concrete  $$.
2 You save the cost and time of the floor guy doing grading. 
  (I also recommend Gary Ford from Lancaster). 
3 The floor will have more time to settle and be compacted reducing the
  the chance of cracks.
  (Grade and FLOOD the floor with water (several times) to compact it and 
    find low spots you will be amazed after the first flood at how many low 
    spots and holes you will have, don't be surprised if the entire grade 
    drops an inch or two.
   
Other things to think about:

1 Floor drains and height (if legal in your town)
2 6 mil plastic sheet under the slab (radon or moisture if the garage turns 
  into something else at a later date).
3 Reinforcing wire. (does not stop cracking but will keep concrete together).
4 Floor sealer mine went on as soon as the floor was dry enough to walk on
  without marking. (recommended by Gary Ford helps to slow curing of the
  concrete by reducing the water loss. the slower your concrete cures the 
  less likely it is to get cracks, the bottom plastic also reduces loss).   
5 Finish should not be super smooth unless you like to skate to you car.
6 NO aprons extending beyond the foundation they WILL heave and crack.
7 Protection from dogs, cats, kids and wives wet concrete is like a magnet 
  don't assume anything unless you like long lasting memories.
8 What about steps you can set them up and have them poured with the floor.
  (I built mine with wood, things have a way of moving in our house and a 
   pry bar is easier to use than a jack hammer. :^)

My floor has been in a year I used plastic under and sealer on top and have 
no cracks in the main floor. I have two hairline cracks (expected) in the 
6" wide  piece that sits on the outside of my thermal break. My basement 
floor done 5 years ago (also by Gary Ford) used just the plastic under it 
has 1 hairline crack  2' long on a corner (predicted by Gary when he priced 
the job) because of the shape of the floor lots of angles.

Good Luck

Don                                                      

    I may be getting a large air compressor that stands up on end (5hp/60
    gal tank).  It has three legs with bolt holes in it and it will be
    going in the garage with a cement floor.  How do I go about drilling
    holes for the bolts and what type of bolts or screws do I use?
    
    Dave

    Best bet is to set lead lag shields into cement holes and then bolt
    the compressor down using lag bolts into the lag shields.  The lag
    shields expand slightly when the bolts is snugged down.....causing
    the shield to grip into the cement.
    
    I used a 1/2 electric "hammer" drill with aan appropriately sized
    masonry bit.  Its important to use a low speed htorque drill for
    this type of work. Go slowly and stop periodically to clear the
    hole of dust and to allow the drill bit to cool.

    I  suggest  you do not bolt it down.  Instead, put  the  feet  on  hard
    rubber  pads, perhaps pieces of car tires ( I use 2" thick  stiff  foam
    rubber, but my tank is horizontal ). 
    
    Why?  From my experience the compressor makes more noise if it is  on a
    hard concrete floor.    Also,  I  believe  (but  don't have proof) that
    bolting the compressor down firmly allows more vibrational stress to be
    transferred to the tank by the vibrating pump. 
    
    If you just stand the  compressor  on  the  bare concrete floor with no
    pads it may walk around when it runs.
    
    If you insist on bolting it because you are afraid it will fall over, I
    suggest you bolt it to some sort of vibrational isolators, even if they
    are made from pieces of car tire, etc.

    I want to secure it somehow since the compressor motor sits on top of
    the (vertical) 60 gallon tank.  Using pieces of tire to dampen the 
    vibrations sounds like a good idea.  I'll just get longer bolts.
    
    Thanks
    Dave

    
    I left mine (5hp/60gal) on the skid it was shipped on.  Works fine.
    
    Andy
    

     Made a frame out of 6x6 landscape timbers for my 5hp/80gal vertical
    compressor. Left the front open for easy access to bottom drain.
    Works great, and doesn't tip at all.
    

    re: 15  So I gather you didn't secure the 6x6's to anything?  Is it
    secure enough so it doesn't wander when the compressor is running?
    
    Dave

    Dave, too bad it's not a horozontal tank model. I put my 85 gal.
    tank and comp. head on the second floor. Well, sort of, it hangs
    from a steel "H" beam that is part of my shop wall. A compressor does 
    nothing but take up floor space. (we all know how valuable floor space
    is) It's also quieter. 
    
    The Mad Weldor....Jim

    But the foot print of this isn't too bad, around 2 ft square.  Looks
    like I'll be getting it in about a month, unless I burn the 1/2 hp one
    out before then.....
    
    Dave

    re.16 Nope I didn't secure the 6x6's to the floor, just lagged the 
    compressor to the 6x6's. Hasn't moved at all in over a year it's been
    installed.
    

    I recently purchased a home, and one of the problems that it has is
    that the garage floor has some pretty good holes. I was wondering if there
    is any special way that this problem should be addressed, or is just
    filling the areas with concrete sufficent. I really don't want to have
    the whole thing dug up and done over. At least at this time.
    
    Bob Brister
    
    

This note has been temporarily write-locked pending approval of the author.

To the author:  This subject is already under discussion in this file, under the
topics listed in the title.  Please look at these notes; you may find that your
question is already answered, or you may find a note where your question would
be an appropriate continuation of the discussion.  Note that since nearly
everyone uses NEXT UNSEEN to read notes, your question will get the same
exposure whether it is a response to a two-year-old note or it is its own new
note. These topics were found using the keyword directory (note 1111), and you
may find other notes relating to this subject by examining the directory
yourself. 

We do, however, welcome new notes if they explore a specific aspect of a 
problem that may be under general discussion.  And this moderator has been 
known to make mistakes. :^)  So if after examining these notes, you wish to 
continue the discussion here, send me mail.

Bruce [Co-Moderator]

    I used a product manufactured by Bruning Paint Company called
    "Concrete Stain" when I painted my garage and basement floors.
    I'm very impressed with the stuff.  It is a paint product, but
    NOT a paint that forms a film on TOP of the concrete; the stain
    penetrates the surface (kind of like Danish Oil for wood) and
    seals the pores of the concrete.
    
    Since it is not on TOP of the concrete it is nearly impossible
    to chip or flake (unless you chip the concrete!).
    
    The concrete must cure for at least 30 days prior to application,
    and etching with muriatic acid is recommended.  Drying time is a
    function of temperature and air circulation; the basement took a
    lot longer to dry than the garage because I wasn't able to vent
    the fumes as easily as in the garage.  I'd allow several days to
    ensure complete drying.
    
    Retail price is around $15/gallon; kind of steep, but it seems
    to perform well.

(Didn't even know where to look in 1111)

I'm going to build a storage building/shop/whatever_you_want_to_call_it,
20x24'. Heaviest thing likely to ever be parked in it would be a boat
on a trailer, or a lawn tractor, etc. It will have a garage door type entry to
accomodate the possible tractor, trailer, etc. The idea is that it will
be 50/50 use between storage area and workshop.

I'm having trouble deciding on a concrete slab vs. a wood floor on
sono tube supports.

It won't be heated, so the slab is bound to crack, but that's not the
end of the world. I'm assuming that other than appearance, there's really
nothing wrong with a cracked slab, as long as water doesn't get into it.
(Have I missed something?)

The concrete slab would cost $600 or so. I'm guessing a wood floor system
won't be much cheaper. (Anybody got a good estimate?)

I'm not sure about driving vehicles into a wood floor building, even if
the vehicle is only a lawn tractor or 1000# trailer.

Wood floor seems like a lot of work to build, but might be a bit more
comfortable to stand on. The concrete slab sounds a lot more durable.

Anybody got any general suggestions? Have I missed any important
considerations?

Thanks!

Erik

    When you say a concrete slab, I think you mean just a slab on the
    ground.  If you live in a cold climate, that sure will crack.  It
    (the slab that is) also won't do a very good job of supporting the
    structure for too long.
    
    Usually, you pour a frost wall around the perimeter and then the slab
    floor.  If you can get the footings, frost walls, and the slab for a
    20 x 24 building done for 600 bucks, DO IT.  Don't even worry about
    the excavation costs.
    
    If not, the wood floor with tubes seems cheaper.  Figure on $2 or $3
    per sq foot (depending on flooring choice) for a good solid wood
    platform/floor.
    

I should have been more specific.

I am talking about a "Turn-down" floating slab. In other words, 2' or so
depth around the perimeter, and a 4" slab in the middle, poured over several
inches of gravel.

The excavating contractor I've been talking to says to assume that ANY
concrete poured foundation/slab/whatever WILL crack if not heated. He
noted that as long as water doesn't get in to start heaves, its not a big
deal.

The $600 is for the concrete, delivered, trowled, paddled, etc. The total
cost will be a good bit higher. The idea was that I'll spend $400 - $500
in excavation, gravel, etc. either way. I still believe that the cost of
the slab itself as compared with a wood floor will be about $600. I don't
know how to estimate the cost of the wood floor system. It looks like total
cost for the slab installed would be $1000, and total cost to do it on
tubes would be $500 plus cost of the wood floor. If the wood floor will
be $3/s.f., then the slab sounds cheaper. Again, I'm no expert so if I'm
missing something please don't hestitate to correct me...

I'm particularly interested in anyone's advice/experience/ideas with which
type of floor is more desirable for this type of use. The slab seems most
durable/effective, but somehow I get really edgy about the idea of a
concrete slab I know will crack 6 mos after its installed...

Thanks!

Erik

    I used a turndown slab when I built my 24 X 26 garage 6 years ago and
    it still has not cracked. Just be sure to use reinforcing mesh.
    
    bob

What thickness is your 6-yr old slab? 4"? 6"?

Was the garage attached to a building? Used regularly in winter?

(The building I'm considering would be uninsulated and would sit all
winter...)

Thanks again!

Erik

    The slab is 4" thick in the middle.  The garage is free standing and
    is used year round for our 2 cars, the tractor/snowblower etc. The 
    only time there is heat is when I need to work on one of the cars and
    I plug in the "torpedo heater".  The walls are insulated with 3 1/2"
    kraft faced insulation, but the ceiling/roof is not insulated at all.
    
    
    bob

>    I used a turndown slab when I built my 24 X 26 garage 6 years ago and
>    it still has not cracked. Just be sure to use reinforcing mesh.
    
      Frankly, a slab cracking because of not being heated is new to me.
      What I've been told is tha any slab over  the  size  of  a  small,
      one-car garrage is likely to crack.  The larger the slab, the more
      likely and numerous the cracks.
      
      As  for  reenforcing  mesh,  it  won't  make  much  difference  in
      preventing cracks, but it can help in holding them close  together
      so that the don't expand or shift.

    
     My 18x20 shed built on a 4inch slab hasn't cracked in 5+ years.
    
    Brian
    
    ps This is in Central Mass. 

    I think the important thing is good drainage under the slab, so you
    won't get freezing water expanding and applying pressure to the slab.
    As long as the slab is well supported (i.e. evenly supported) on
    well-drained ground, it shouldn't crack.  (Put the mesh in though -
    if it does crack, you want the pieces to stay together.)
    
    Now, wood would be easier on the feet, and warmer; you could insulate
    under the floor, although you'd have to worry abou keeping the
    insulation dry if you used fiberglass.  You could also put foam under
    the slab before pouring it, for that matter.
    
    A wood floor is going to end up being higher above the ground than
    a slab is; if you're going to want to drive into this building, you
    may want a slab simply because you'll have easier access.  Although
    depending on how your land slopes, you might be able to have one
    side of a wood floor virtually at ground level and still have clearance
    under the floor.
    
    I suspect the slab is most practical; the wood may be more comfortable
    in use.

    Buy good, rubber soled shoes, and the concrete isn't too bad.  As 
    previously mentioned, soil type, moisture or water level, and soil
    compaction (or lack of) are what cause cracking.  Cracks aren't the end
    of the world.  
    
    Carl

I rolled my 14 x 20 garage onto a new slab.  The 4" thick "driveway" apron 
cracked but the garage floor is intact.  I excavated to 2 feet myself with
one of those rented baby backhoes and had a wonderful time!  That ran about
$240.  $90 worth of gravel got me about a foot of 1" stone under the pour.
I used mesh and rebar and made the floor 4-6" and with an edge that was about 
a feet deep and a foot wide.  For the following effect.


        |-----------------------|
	|   -----------------	|
	|  /		     \	|
	|_/		      \_|

The apron had no rebar, mesh only and got one crack the first winter.  That
was four years ago.  Actually the first winter, the whole thing rose up an
inch, but the that's the point, it came back down with breaking and the 
garage never knew the difference.  

	I think I spent under $300 for the concrete because I recollect
it took about 3-4 days and came in around $600.  If I were building a shed
I'd probably go with the wood floor so I could move since I'm already thinking
of expanding my house and wondering if the garage is in the way again.  :-)

	But I also think that everybody should get a chance to build something
huge out of concrete.  It lends a sense of permanance to our pilgramage.

Folks:

In case Erik does end up going with the wood floor, are there any thoughts on
special reinforcement needed to support a half ton trailer parked on it for the
winter?

For example, should the drive in area be supported by some significant load 
bearing beams, resting on sono tube supports?  If that is overkill, should the 
joists run perpendicular or parallel to the drive in direction?  Should the
joists be closer together than standard so the floor between them sags less 
under the concentrated weight?  What kind of flooring would be needed (I assume
lots thicker than anything needed for normal walk around flooring)?  Could he
make do by parking the trailer so that all (3?) weight points rest on an extra
plank on top of the floor that serves to distrbute the weight?

Depending on the configuration of beams, joists and concrete supports, the
cost of the wood floor just might be prohibitive.

    
    A standard 2x10 floor should hold 1/2 ton without too much problem. I
    put in a wood stove and a hearth in my house 4 years ago, and this is
    damn close to 1000lbs if not over. The stove alone weighs 300lbs. And
    the hearth is made of brick.
    
    Mike

    It all depends on the span.  Get some safe load tables for wood
    house construction and figure it out.  A really good book (not
    cheap, but really good) for this is "Simplified Design of Structural
    Timber" published by Addison-Wesley, I think.
    It can certainly be done.  A 1000-lb boat trailer is not a big deal.
    A double-bed-size waterbed is somewhere around 1400 pounds, I think,
    although that is a well-distributed load.
    If you got some of that 2 1/4" thick tongue and groove mill flooring,
    that ought to take care of any point loading problems.  
    

Yeah.  It's not the total weight, but the fact that it is distrbuted between
2 tires and a foot (holding up the hitch end).  That puts a considerable load
a few square inches of floor.

Consistent with the sentiment a few replies ago, the actual fixed bid and
the planning estimate of $600 in concrete didn't match up. The fixed quote
is $1400!

Strong lean is now toward wood floor again. I'm condiering building the
whole place out of rough sawn lumber. There's a sawmill closer than the
lumber yard...

I'm planning to use the 50#/sf table to determine a joist span based on
sized wood. I figure that using rough-sawn, a 2x10 really is 2x10, so
it ought to be stronger than a nominal 2x10 sized to 1.??x9.??

The building will be 20x24. I'm figuring 2 floor frames of 10x24 on
three beams supported by sono tubes. Advice wanted on the size of
beams on tubes, and spacing between tubes. Also, the book I have talks
about tables for 1.0 to 2.0 x 10**6 of something (Elasticity or somesuch)
and shows joist spans. I just picked the middle numbers. What should I
be using for rough-sawn spruce from the local sawmill? Also, the wood
will probably be pretty green. Any particular concerns there?

There will be a loft. The tables say I need a 2x12 to span 20' without
an intermediate support. I'd like to avoid lolly (sp?) columns. Any ideas?
All I can think of is getting the sawmill to cut a great big wood center
beam.

Erik

p.s.	JP, what about that lunch you never got back to me on?

    For ungraded lumber, I'd use the lowest numbers in the tables.
    There is no telling what kind of knot distribution you're likely
    to get in the rough-sawn joists, and they can have a significant
    effect on strength.  Commercial structural timber can have only
    a certain number of knots, in certain placements, but with rough
    sawn you have no guarantees.  You may be able to selectively pick
    the pile and do your own grading, to a degree, but I'd still err
    on the side of caution.
    Are you sure the stuff from the sawmill is spruce?  I'd more
    quickly suspect white pine, which is not very strong at all.
    

I'm planning to build a shed -- no vehicle storage, just an 8x12 garden 
shed that stores a mower, 40lb bags of lime, and so forth. I've been 
planning to use a wood floor supported on 4 sonotubes of concrete, but 
this note makes me wonder.  Is a concrete floor preferable in situations
where there isn't a weight problem?  This is in Massachusetts, by the way.

	Thanks,
	Larry

    
    Check with your town about building a shed. In my town (Goffstown NH),
    if I used sonotubs, the shed would be considered a permenent structure,
    thus I'd have to pay taxes on it. I'm sure the same thing goes for a
    cement slab. I put mine on cinderblocks (6 of them). And I used 2x8
    floor joists. I must have at least 1k lbs of weight in there. And I'm
    sure I can put another 1k in there without any problem.
    
    Mike

I build my garden shed on a concrete slab and it worked out really well.
It's 12x15 and the floor is a turned down  slab like the one mentioned 
earlier in this note.  I decided on concrete instead of a PT floor 
because the concrete:

1) will not rot
2) is easy to clean up - oil spills etc.
3) will not break/splinter
4) wasn't a whole lot more expensive than a PT floor
 
I was curious to see if the floor would crack, but it made it through 
the winter with no visible damage.  Even if it does crack - big deal, it
will match my cellar floor :-).

You might have a hard time getting someone to deliver the amount of 
concrete you would need for an 8x12 slab.  As I recall, the amount I 
needed was just under the minimum amt for delivery (they delivered it 
anyway since it was local - BROX in Hudson NH).  If you get some help and
a cool day, maybe you could rent a mixer?

-Tom

Over the weekend our washing machine incoming cold water hose ruptured all over
our finished basement. We didn't realize it for about 1/2 hour. My shop vac
took up @100 gallons of water.  We pulled up all the carpeting and dried them
outside (thank goodness for a dry weekend). Linoleum that was under the
carpeting was thrown out. 

That left the concrete floor, and a very musty odor. We surface dried the floor
with fans and then put a dehumidifier into one of the rooms. By this morning,
we weren,t getting much water, much of the musty odor was gone (but not all)
and moved the dehumidifier to another room where more water seems to be
collecting.

	First of all, have we handled the situation properly?
	Second, how long before we can put carpeting and furniture back in.
	Third, do we need to reseal the floor? I sealed it about five years ago
when the floor was poured with three coats of sealer.
	Fourth, what else should we/could we do.

	We want to get the place back in order (everything is stacked at one end
of the basement), but we also don't want to redo everything.

All advice accepted!!!!!!!!!!!SANFORD!!!!!!!!!!!!!!!!!!!!

    
    
This note has been temporarily write-locked pending approval of the author.

This subject is already under discussion in this file, in the topics listed in
the title.  Please look at these notes; you may find that your question is
already answered, or you may find a note where your question is an appropriate
continuation of the discussion.  These were found using the keyword directory
(note 1111), and you may find other notes relating to this subject by examining
the directory yourself.  Nearly all the people likely to respond use NEXT
UNSEEN, so a response to an old note will get the same exposure as a new note. 

We do welcome new notes if they explore a specific aspect of a problem that may
be under general discussion.  And moderators do make mistakes. ;^) So if after
examining these notes, you wish to continue the discussion here, send mail.

Bruce [co-moderator]

If you choose to bolt to the concrete floor, the elegant approach is
to use a hammer drill or power rotary hammer to drill concrete holes.
Rather than using lag shields (only DIYers use 'em), use anchor bolts.
Anchor bolts have a flared end and sliding collar that tightens inside hole
as bolt is tightened.  Your home variety drill *won't* work for this.
Without the hammer action, the bit will wander as it encounters aggregate in
the concrete, yielding an over-sized hole which the anchor bolt won't work in.

Anchor bolts are cheaper than a lag screw + lag shield, require a smaller
hole, don't require spotting the hole, and are probably result in a stronger
attachment.    

I just bought a bag of 3/8" x 3 3/4" anchor bolts @ $0.61 including
nut and washer.  The equivalent lag screw/shield/washer solution is
@ $1.15.  Anchors allow me to drill 3/8" holes, lags shields require
5/8" holes (BIIIG difference when drilling concrete).

	Randy Marks

    Can you put tile on a new concrete floor or should you let it 'cure'
    for a while?  We are considering having a house built, but we want to
    start with the basement finished, with either vinyl or asphalt tile on
    the floor....  What's the minimum waiting time between pouring the
    foundation and finishing the basement?
    
    Willie

    I'd say to wait at least till the spring thaws come (assuming you're in
    snow country) so that you make sure the basement is DRY!
    
    Eric

    We have a painted basement floor. As soon as the floor gets wet, the
    paint starts to come up.  It peels up and makes a slimy mess that gets
    tracked all over creation.  Spill a little water, and if you don't pick
    it up immediately, there is a peeled spot on the floor.  If you run the 
    shop vac over the floor, it scratches.   
    
    The floor was painted when we bought the house.  We ruined that paint
    job by mopping the floor. Of course the paint doesn't entirely come up.
    The painter said that the only thing to do was to repaint the floor,
    and to avoid getting it wet.  
    
    This week, the drain under the house clogged, and we got a inch or so
    of water on the floor.  The new paint is now ruined.  This drain is not
    in the basement; it diverts water from behind the house through a pipe
    under the house to an outlet at the base of the lawn.
    
    The ground under the house tends to be wet.  When not clogged, the
    drain keeps the basement dry.  
    
    What can we do with this paint?  Is there any way to remove it? 
    It is the worlds stupidist treatment for a concrete basement floor, 
    since it can't get wet.    
    
    We would like something for the floor that is smooth, washable, cheap,
    and not ruined by water.  This is a workshop.  Sooner or later, something 
    is bound to leak again.
    
    Thanks,                      
    Margaret.  

I painted the floor in my garage and it constantly gets wet.  It hasn't peeled
at all (except where there was oil, or where tires have spun in place on top of
the paint 8^)

It was paint for use specifically on concrete floors.

-Al

    Our basement was painted with concrete floor paint also.  I beginning
    to suspect that there are different types of concrete, some of which
    paint up ok and some of which do not.
    
    

    I believe concrete needs to be "etched" with acid (muratic??) before it
    can be painted.  Maybe this wasn't done?
    
    Chet

    I believe it was either HOMETIME or "FROM HOUSE TO HOME" that recently 
    showed the steps to painting a basement floor. They recommended 
    something like this:
    
       1. Sweep AND vaccuum the whole place.
       2. Wash it with strong detergent and water.
       3. Rinse thoroughly and allow it to dry for a few days.
       4. Go over it with muriatic (I think) acid.
       5. Rinse thoroughly and allow it to dry for a few days.
       6. Paint it with special paint.
    
    They STRONGLY stressed that although it is a slow and tedious 
    process, any shortcuts will likely result in flaking.
    
    							-Mac

    RE: .14
    
    I did the same thing, minus the acid. Worked fine.
    
    Marc H.

I didn't use the acid, either.  I cut corners in terms of cleaning the old oil
spots as well.  The only real bubbling/flaking has been where the MG has leaked
brake fluid.

I'm going to be painting the garage floor at my new house and want to be sure
that it isn't so slippery when wet.  I just got off the phone we Nashua
Wallpaper.  The guy said that you add "skidtex" (sp?) to the paint to keep it
from being so slippery.  The tradeoff is durability, but it keeps you from
killing yourself.

-Al

    there are "sand" type additives that can make almost any paint skid
    resistent.   If you have trouble finding them at a home or paint store,
    try a marine supply.
    
    	Dave.

    Alternately, just take a couple of handfulls out of the kid's sandpit.
    
    If its thick paint, mix it into the paint, if its thin paint, sprinkle
    it on as you go, and paint over it with the second coat.
    
    No worries, mate!
    
    regards,
    Michael Watts.

    This may be a silly question but here goes.
    
    What are the benefits of a painted garage floor?
    
    
    Joyce
    

RE:  a couple

I thought of just adding sand, but since there is a special product for it, I'd
like to have a look to see if its more than just sand.

RE:  last

There are a few of benefits, in my opinion...

1. The most obvious one is that its easier to clean and keep clean.  You can
sweep a cement floor 20 times in a day, and each time, the broom will raise some
dust and you'll have something to put into the dustpan.  The painted floor won't
do that because the paint is keeping the concrete from wearing away and
generating dust each time you sweep it.

2. Spills are easier to clean up because they don't sink into the concrete.

3. The musty smell of wet concrete is eliminated.  To most people that might not
matter, but since I'm restoring a car, I spend quite a bit of time in the garage.
Some of it is actually laying down on the floor.  The painted floor is a much
more pleasant surface to lay down on when compared with raw cement.

-Al

    Excellent points Al, thank you.
    
    Joyce

    I hope someone can help me.  I have checked the keywords listings
    and found nothing that resembles my problem....so here goes.
    
    I just bought a new OLD house and the previous occupant put a floor
    down in the kitchen that baffles me.  It seems to have been poured.
    I feels like vinyl, but what it really is (I found a bag of the
    stuff in the cellar) is chips of color which was added to some
    clear compound that hardened and now is IMPOSSIBLE to remove.  Or
    so it seems.  It is about 1/2 inch thick and firmly adhered to the
    3/4" plywood underneath.  Does anyone out there have any clue as to
    how this can be removed? 
    
    A friend already suggested a jackhammer.... :-)))
    
    Nancy

I don't know how to remove it, but I do know someone who had one installed.
You're right about the process -- they pour some goop, sprinkle it with
chips, and top it off with more goop.

    I suspect you have two alternatives:
    
    1. Leave it there and put something else over it;
    
    2. Tear out the whole floor, plywood included, and rebuild from the
    floor joists up.  
    
    Alternative #2 may not be as bad as it sounds, if one can cut through
    the stuff with a circular saw (using a blade, no doubt, one is willing
    to throw away afterwards!)  The time saved in ripping out may more than
    make up the cost of new plywood.  Just (easy to say!) cut the floor into
    manageable pieces and pull it out.  The only problem I see is getting
    under the front edges of the cabinets to cut.  If the stuff is basically 
    not cut-able, or if it totally gums up a sawblade...well, it will be 
    more difficult....
    

    No help but just as an aside, this sounds like the stuff they put down
    in the restrooms in Salem about a year ago.  When they were working on
    it it looked like they squeegeed some goop down (like applying driveway
    sealer) and then added the chips.  Actually, maybe Facilities in Salem
    can give you the name of the people that applied it.  Perhaps they have
    a way to remove it.
    
    George

    
      
    If it's what I think it is, it is called "seamless" flooring compound.
    The "chips" are resin in a urethane or binder - there's another "hard"
    kind that uses epoxy - similar to the composite countertops and more
    expensive to install. If it's urethane, and is  just beat up, it can be
    polished renewed by adding another layer of urethane.  It's pretty
    hardwearing to anything except direct heat.
    
    If you hate it, it will have to be sawn up (some used glass or stone
    chips, which are buggers to saw). Trouble is, it did not have to be
    installed over an underlayment, so you might have to take up the
    subfloor. The dust from sawing is dangerous stuff.
    
    I don't think you can install vinyl flooring over it without adding
    a luan underlayment - you might want to check with a supplier to see
    if their warranty would be void.  The hard kind does form a good surface
    for vinyl.
    
    Colin
    

    My dad used to have a lot of this stuff installed in kitchens of homes
    he built in Florida.  There, the stuff was applied directly on the
    concrete slab.  I believe that the one of the original brand-names of
    it was  "Decra-lon".  I also remember talking to the painters who
    installed this -- they soon learned that they either needed very good
    ventilation or very good vapor masks.  The fumes were very "glue-like".
    
    Mark L.

    
    Thanks for all the replies...it is just as I suspected.  The worst part
    is that the room is 16 x 20, half of it is the poured floor and half is
    plywood.  I had to rip up an old carpet that was stained beyond belief
    because my animals kept insisting on using it as a toilet (the former
    owner had about three dogs and two cats, need I say more?).  So at the
    moment, I am living on a plywood dining room floor abutting a poured
    kitchen floor.  My ultimate goal is to put down hardwoods through the
    whole area, so I guess the only alternative is to rip up the poured
    floor, plywood and all.  To stack more plywood on top of the other 
    plywood (to even out the drop between the poured floor and the dining
    room) would elevate the floor to a point where it woud be about 3
    or more above the living room floor (which abuts the whole darn thing).
    
    (sigh)
    
    Just another lovely home improvement project.....and tons of money!!!
    
    :-))
    
    thanks for all the replies!  
    
    Nancy

    I had this in a previous house - there was some already there when
    we bought it, and we had more installed when we expanded the house.
    It's wonderful stuff, but you can't remove it.
    
    			Steve

    Can someone explain the benefits/uses for such a floor? Is it very hard
    wearing? Would you use something like this in a mudroom or at a summer
    cottage?

The major advantage that I can see is no seams.  The one I've seen also
looked very good.

My only experience was with my parents house.  The floor was in the original
construction in 1969 and still looked OK in 1991 when they covered it.  That's
a pretty good wear rate.

Al

The other advantage I could see would be to level the floor.  If there is a
good deal of tilting in the floor due to settling with age, a poured floor
like this should turn out fairly level.  This assumes of course that the
material is still in a free flowing liquid state when poured, rather 
than a fairly thick pasty state which would have to be smoothed by hand.

PeterT

    	Sounds like the stuff would be pretty rigid. Can anyone think of a
    reason why you wouldn't be able to just glue luan to the surface and
    just use that for the new flooring ?
    
    	Ray

>                        -< Why not just luan over it ? >-

	Depends on whether you want the new floor raised above the
	surrounding rooms or not. A level of luaun over the original floor,
	plus the thickness of the new flooring material, may not be all that
	great if you have hardwood fllors elsewhere.

	Roy

First of all, you may not be able to find a supplier/installer nowadays.
Poured floors were popular in the 60s and 70s, but died out after that.

The problem with gluing luan is that the surface is not smooth - it is sort
of "pebbly".

				Steve

Friends in Brooklyn NY just had one of these done a year or so ago.

    
    That's the problem I would have....if I put more plywood over that 
    floor it would raise the kitchen/dining room floors a good 3-4 inches
    over the living room floor that abuts it.  
    
    The stuff may be tough...it may be seamless...it may wear well....but
    when someone picks out chips in tomato red/tobacco brown/cream and
    black....all this against walnut panelled walls, walnut cabinets, and a
    rust shag carpet...
    
    GAG!
    
    Nancy (who plans to rip the whole thing up!)

I wonder if another poured floor could be put directly on it, and if so how
much it would be raised.

    A friend who worked for Kyanize paint put the epoxy type on the
    basement floor (playroom, workshop, laundry).  I'd think that would be
    an ideal application.  
    
    Carl
    
    ps. I was going to suggest heat to melt the stuff off, since plastics
    generally melt at 400 to 500 degrees F.
    
    

    	The luan that I was thinking of is the 1/4" thick stuff. Adding the
    thickness of sheet vinyl to this would raise the whole floor by less than 
    1/2". As someone else mentioned though, this may even be too much
    depending on the height of the surrounding floors. Just a thought.
    
    	Ray

    
    And all I wanted was to put hardwood floors in......  :-)
    
    What aggravation!

    Ah - the mournful lament of the DIYer: "All I wanted to do was..."
    
    Welcome to the (ever-expanding) club! 8-)

    
    :-)))  Thanks!  My friend Deb said to me, "Ahh, a beautiful 200 year
    old home --- that will need DAILY cash infusions to keep it happy."
    
    
    N

    
    
    Is it possible to paint a sealed floor? The floor in question is the
    garage floor, during the winter months road salt drips from the 
    wheel wells and took the sealer off the floor, it is now starting
    to eat away at the concrete itself. I would like to repair (fill)
    the spots and put some sort of paint or something down that will resist
    the winter road-salt corrosion of the concrete. I think it may be a
    losing battle......but never question Yankee Ingenuity!!
    
    
    
    
    thanx in advance
    
    Bill

We are wanting to seal a fairly new garage floor.  I think it has been 
approx 60 days since the slab was poured.  With `stains' that seal floors
they suggest waiting at least 90 days.  On the sealers like Thompson's
there is no mention of waiting.  In fact, one not a well known brand we 
were looking at said sealing would help in the curing.  It was also 
paraffin based.

Does anyone in here have an opinion re: paraffin based sealers for 
garage floors.  How should the floor be prepared?

Judy

>>    <<< Note 1252.23 by GENRAL::KILGORE "The UT Desert Rat living in CO" >>>
>>                         -< Sealing garage floor.... >-

I just had my garage slab poured and the contractor recommended
"KURE N SEAL".  I got it at Corriveau-Rothiers" in Nashua for $54 for
5 gallons.  I was told to put in that evening after the pour and then
maybe again in a couple of months.  It's got some real nasty chemicals
in it and lots of warnings about having adequate ventilation.  It's
supposed to seal and help with the curing process.

Garry

    The floor under my 16' garage door has risen a couple inches over the
    years. As a result, the door no longer closes properly and leaves a gap
    at either side between the floor and the door. Short of digging up the
    floor and pouring a new one, is there any way to fix this? 

Pour a new one over the top of the old one and adjust the door tracks 
upward so the locks engage properly?  The old floor was most likely too 
thin in the first place.

If the gap isn't too big, you could try to cut/shave/trim the bottom of the door
so that it matches the shape of the floor.

-Rob

    You might also try attaching a rubber gasket along the bottom of the
    door.  Then, as the door comes down, the rubber will adjust its
    shape to follow the contour of the floor.
    

    
    Assuming it's a concrete floor you could call in a contractor with a 
    floor grinder to remove the hump. A floor grinder is a brute force 
    tool... picture a floor buffer with big carbide blades instead of a
    polishing pad. Humps, concrete spills and bad pours are the reasons 
    that floor grinders exist.
    
    								- Mac

Don't do anything drastic until you have some assurances that the settling
or heaving won't keep going.
It would be a shame to repour a floor or shave the door bottom or gouge
the hump and find a year or two later that the heaving/settling hadn't
quite finished.

I vote for the rubber gasket.  It will adapt to continuing changes
over some range if the situation is not quite stable.

- tom]

Perhaps the problem isn't with the garage floor at all.

What kind of foundation is under the garage itself.  Is the garage settling, 
maybe?

    I'm having a garage floor poured (in Mass.) and they are using concrete
    with fiberglass embeded in it rather than using wire mesh
    reinforcement.  Does anyone have any comment on this about whether it's
    better, worse, or the same?  The guy pouring says that it's much better
    (stronger), but of course he's selling it.

    Thanks,

    ---Phil

              <<< Note 161.230 by HANNAH::MCKINLEY "Nota bene" >>>
                         -< Concrete with fiberglass >-

    I'm having a garage floor poured (in Mass.) and they are using concrete
    with fiberglass embeded in it rather than using wire mesh
    reinforcement.  Does anyone have any comment on this about whether it's
    better, worse, or the same?  The guy pouring says that it's much better
    (stronger), but of course he's selling it.

    Thanks,

    ---Phil


	They discussed this on TOH a few weeks ago and the general
	feel was that it's stronger that using the wire mesh. I
	have no personal knowledge other than that. When in
	doubt, use both I guess :-)

	Red

    
    My guess is the fibers are better for local cracking such as shrinkage
    cracks and the like, while steel mesh should be better for larger
    cracking such as slight settling or shifting problems.
    
    I'd have no qualms of using fibers poured over a well prepared surface
    (sand or crushed rock brought in and compacted), but would want to use
    steel mesh if I had any doubts.  That said, steel mesh is obviously more
    expensive in terms of material and installation costs, plus as you are 
    pouring you need to make sure it gets up off the bottom of the slab 
    to somewhere in the middle (i.e. more labor).  The fibers are added
    at the source and require no site labor.  Also in favor of fibers is
    that they don't rust, so you don't run the risk of rusting steel mesh
    expansion and cracking (doesn't happen often, depends on moisture
    problems if any).
    
    Are they willing to guarenttee against cracks?  And if so, what/how
    will they repair?

    They guy who was in charge of doing the concrete said that this was a
    "small" pour (24'x26').  He said cracking should not be a problem, but
    didn't give any guarantees.  He said that when they have to break up
    a concrete & fiberglass pour (during a building demo or something),
    it's really tough to do the breaking.  It's not just pound it with a
    sledge and it breaks up, the fibers hold it together.

    I'm just checking here to see if anyone knows how much of this is sales
    talk and how much is true.

    ---Phil

    I expect it's virtually impossible to guarantee concrete won't crack.
    One can take reasonable precautions, but you're stuck with the basic
    problem that concrete is not very strong at all in tension.  That's
    what the fibers (or rebar) help out with, but in the final analysis
    you're dealing with concrete.  It's brittle, and not very strong when
    it's pulled on.  (Strengh in compression, on the other hand, is where
    concrete is a big winner, but that doesn't help much preventing cracks.)
    
    So...have as solid a base under it as you can get, reinforce it with
    rebar (or fibers), don't have "too big" a slab without an expansion
    joint, use good concrete, and hope for the best.  But it may still 
    crack.

    A friend just forwarded the recent fiberglass in concrete question to
    me as we spec'd that in the concrete slabs for the basement and garage 
    of our new house.  Despite the fact that it should strengthen concrete,
    both our basement and garage floors have hairline cracks.  While I'm
    not sure what would have happened with mesh (and I'm assuming there 
    really is fiberglass in the concrete as spec'd), the fiberglass did
    not seem to stop the cracks from occurring.  Luckily, they do not seem
    to be a problem other than the visual aspects (so far anyway).

    
    	I want to put a plywood floor over a concrete floor (converting
    	garage to a finished room), using 2 x4's, either nailed or glued.
    	The concrete floor is uneven and slightly sloped.  How do you level
    	the subfloor?  Do you use wood shims under the 2x4's or do you shim
    	between the 2x4's and plywood?  What is the approach?
    

>    	the subfloor?  Do you use wood shims under the 2x4's or do you shim

    Shim the 2x4s and then you'll have a nice smooth, flat and level
    surface to attach the plywood to. Put some foam insulation
    in between the 2x4s for some extra insulation.

    The only thing that I'd watch out for thou... is that many garage
    floors are sloped several inches from back to front. I think that
    my garage floor slops about 5". That's a lot of shimming!! You'd
    probably have to re-think your plan if it slops this much.

    Charly

    re: .237
    
    Yes, there's some legal requirement (at least in Mass.) that a
    garage floor slope some minimum amount towards the door.  I assume
    it's so gasoline fumes, if any, will drain out.  I found out about
    this when I got a new garage floor poured.

    my parents did this about a year ago ... the contractor put down 3-4"
    of styrofoam and poured new concrete on top of it.  i thought it was a
    strange way of doing it, but it turned out great.

>    Yes, there's some legal requirement (at least in Mass.) that a
>    garage floor slope some minimum amount towards the door.  I assume
>    it's so gasoline fumes, if any, will drain out.  I found out about
>    this when I got a new garage floor poured.
    
    Actually I suspect it's so water will flow out as it melts from the
    snow and ice on your car, since (as I understand it) it's against
    code to have a drain in a domestic garage because that might
    encourage people to pour waste oil and other such no-nos down the
    drain.

    	The "waste oil down the drain" is not what I suspect the reason is.
    It's not much more difficult to pour waste oil down a slop sink, which
    you can legally install in a basement.
    
    	I suspect the real reason has to do with "in the event of an
    accident". For example, if you have oil heat and your indoor oil tank 
    leaks, where's it going to go ? There is also no guarentee that a house 
    with one kind of heating system won't get converted to another. The same 
    thing could happen with a gas tank leak in a car, and there are probably
    other examples too. 
    
    	Although these things may be unlikely, the cost of cleaning up one
    of these messes has growth exponentially over the years. If it did
    happen, you could be talking major $$$. Guess the powers that big
    figure the minimal convenience is not worth the risk.
    
    	Ray

Would a gasoline leak in a car pollute the ground?  I suspect the gasoline
would vaporize.  The gasoline tanks that cause ground pollution are the
underground ones that hold hundreds or thousands of gallons.

>     Actually I suspect it's so water will flow out as it melts from the
>    snow and ice on your car, since (as I understand it) it's against

    That's not a bad reason either, but I think that the real, legal,
    saftey reason is for a gasoline leak. The gas will vaporize, but
    the gas fumes are heavier than air and will sink to the ground. A
    floor sloped to the garage door will direct and move the fumes out
    of the garage.

    We have a door in the back of our garage that leads down to the
    cellar, and we had to provide a 4" to 6" lip there to prevent the
    fumes from traveling down to the basement. 

    Gasoline fumes, travelling down to the basement and finding the
    oil burner can great a BIG mess!!

    Charly

    
    My concrete basement floor seems to be very soft and as a result
    quite dusty. The dust actually kicks up and finds its way in to
    the upper level of the house. 
    This is in a new (less than 6m old) home. 
    My question, will the  floor harden in time, or is there a problem
    with the concrete used when the floor was pored. Is there anything 
    I can do to correct the problem. 
    
    thanks in advance

    I think you're stuck with what you've got.  Concrete does continue
    to harden over time, but I don't think it will help what you're
    seeing.  Besides, the hardening is asymtotic, and after about 4
    weeks, certainly after 6 months, the increase gets to be *really* 
    small.
    It might not have been cured properly (allowed to dry out too fast),
    or it might have been poor concrete to begin with, but it's probably
    not going to change.
    Your best bet is probably to sweep/wash/vacuum/whatever really well,
    then apply a good durable sealer or paint of some kind.
    

    I believe "dusty concrete" was one of the problem mentioned by
    the guy doing my cellar floor if the concrete used was too
    "soupy".  The mix they used on my project was extremely thick,
    and they had to wheel-barrow it throughout the basement.  He
    said some contractors will try to save a few bucks by using a 
    mix that is fluid enough that it can be shot right out the truck
    and just be allowed to more or less flow throught the basement.
    
    FWIW
    
    Vince