| Title: | Home_work |
| Notice: | Check Directory (6.3) before writing a new note |
| Moderator: | CSLALL::NASEAM::READIO |
| Created: | Tue Nov 05 1991 |
| Last Modified: | Fri Jun 06 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 2100 |
| Total number of notes: | 78741 |
In the next year or two, I'd like to finish off part of the attic
in my circa 1900 colonial.
One of my concerns is the fact that the floor is supported by 2x8
joists spaced 24 o.c. running a 13 foot span, from the center of
the attic (in line with the roof peak) out to the edge of the attic
(where they meet the roof rafters, also 2x8). My concern is that
the floor is not sturdy enough -- when I stand at the center of
the 13 foot span, and jump lightly, I can feel definite movement.
I'm considering ideas for strengthening the floor. Here's my
proposed solution:
Since I plan to build a kneewall when I finish the attic, I thought
it would be good to use the kneewallstuds to securely tie the floor
joists to the attic rafters, and thus gain for my floor the added
strength of the roof rafters. The kneewall would be approximately
5 feet fromthe edge of the attic, and thus somewhat close to the
center of the 13 foot unsupported span of floor joist. I would
probably use lag bolts to secure the kneewall studs to the rafters
and joists.
My question to you all: is this an appropriate solution to my problem?
Can I expect it to significantly improve the sturdiness of the floor?
Is there potential for overstressing the roof structure?
Is there a better way?
Thanks,
Joe
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 28.1 | A concave bow roof? | CSMADM::MARCHETTI | Fri Mar 18 1988 16:21 | 6 | |
You ought to check with your local building inspector. I am adding
a level to my ranch, and they require sistering 2x10s to the existing
2x6 joists. Although you will be supporting the new floor close
to the center of the span, you will be pulling on the roof rafters
nearly in the middle of THEIR span; the worst possible place. The
roof is designed to support shingles and snow, not a floor and furniture.
| |||||
| 28.2 | NETMAN::SEGER | this space intentionally left blank | Sun Mar 20 1988 13:49 | 18 | |
re:-1 I'm afraid I have to disagree... It is a VERY common practice to use a roof to support a floor - though I'm not sure this necessarily applies to living spaces. The weight of a floor is probably a lot less than a roof heavily laden with wet snow. For example, the ceiling of my 24X24 garage has no supporting columns! All the floor joists are suspended from the ceiling and it's VERY solid when waling up there. I've also seen some new houses with attic spaces this suppored. So, if one had a 13' 2X8 suspended at the 5' mark, that would result in only an 8' span which sounds like it should be strong. However, if you want to be official, you may want to check with the building inspector. As far as using lag bolts, I wouldn't bother. I'd suspect 16d nails would be as least as strong, a lot cheaper and certainly quicker to install. -mark | |||||