My current plan is to sheath my cabin with foil faced foam board which means I'll need to put diagonal bracing in my walls. My question is it enough to place braces only at the corners or do I need braces in the middle of the walls as well? Also how does bracing using 1x4" lumber inlet into the studs compare strength wise to osb sheathing. Is there a best way to brace? Option B would be to put osb on the corners and use foam on the rest but this seems a bit of a waste if the bracing will do the job. There are no inspections here but I still want a solid house. I assume foil faced foam board doesn't need to be covered with felt? I'd be open to other suggestions as well.
Scott
ORNL recommended using 1/2" OSB + 1/2" foam sheathing on the corners with 1" foam sheathing on the rest. I think the foam board performs the same function as the felt (as a water plane) so having one on top of the other would seem kinda redundant. What part of the country are you in?
BTW, there is a LOT of information available there (Oak Ridge National Laboratory):
http://www.ornl.gov/sci/roofs+walls/
Bob
I've almost completed our place this last week and I switched plans mid way through. There were enough rookie mistakes and re dos on level one that I decided to sheet the whole thing. My original plan was sheeting on the corners with half inch foam, and one inch on the rest. I sheeted it all and put one inch over that. I am very glad I did that. I may have had special reason for concern though. Actually there is more lumber in my upper unit than in the lower floor. I have huge gambrel trusses, some double and four dormers with lots of heavy rafters. I bet my top is one half again as much the lower.....double counting the shingles. I feel I needed all the sheeting. I was pulling walls with my van to straighten them out..... yet when I sheeted some of it I couldn't tilt the walls any longer. huge difference.
I argued for my earlier plan, but then jumped ship..... and glad I did.
Thanks for the link Bob. I am building in NE Oklahoma.
Frank i originaly planned to sheath the whole thing in osb but like the idea of foam on the outside but I'm too cheap to do both. The house I live in now has braced walls and it hasn't fallen down for over 100 years now though it does seem slightly tilted.
Scott
QuoteThanks for the link Bob. I am building in NE Oklahoma.
Frank i originaly planned to sheath the whole thing in osb but like the idea of foam on the outside but I'm too cheap to do both. The house I live in now has braced walls and it hasn't fallen down for over 100 years now [highlight]though it does seem slightly tilted[/highlight].
Scott
I think that might answer your own question!! I would sheath all of your exterior walls!
QuoteI think that might answer your own question!! I would sheath all of your exterior walls!
Ditto.
I have been reading a lot about this (especially bracing steel framed walls). There are a lot of questions about the strength of let-in 1x4 bracing and steel x-bracing bracing. The general consensus is that full structural sheathing is stronger by far than the 1x4 let-in bracing and x-bracing. Which is really bothersome for me as I'm planning on building with steel to avoid termites.
I think, but have not found anything online to support the notion, that putting bracing plates at the bottom and top plates at every stud may be just as strong as full sheathing. That is, I think the majority of the structural sheathing serves no structural purpose. Think fully sheathed truss versus a truss with just the normal gusset plates.
I built a demonstration broadband over powerline scale model for some friends to use when they were talking to venture capitalists/angels, basically a large 2x4 footed "H" with 1" holes bored to feed some powerline through. I braced it with OSB triangles at the intersections of the 2x4 studs, held in place with a bunch of bugle screws. Not even the marketing guys could screw it up (and they did bounce off it, "accidentally"). One EE PhD called it a "bad design", but that was after he'd tripped and fallen over it (without damaging anything but his pride). LOL. Guess I shoulda painted it yellow.
I think the same thing could work here. I'll probably try the same thing, but with metal plates. Will experiment in the garage with some 33mil studs next week. Will have to bug some civil engineers to model the stresses, I suppose, but I think I can find one of them. Although he isn't too civil when he's been drinking.
Does that make sense?
Bob
Thanks fo the input guys. The foam sales lititure says bracing is fine but you guys seem to disagree so maybe I'll just go with osb. This house is so small I wouldn't save much energy anyways. Too many choices.
Scott
We have the info here somewhere. Inadequate bracing causes the lean Scott noted. Over the years even hundreds of nails on an improperly braced wall will give enough to let it start leaning.
Here is John's post on the comparative study of wall bracing by Charlie Wing.
(//%3Cbr%20/%3Ehttp://www.countryplans.com/images/wall_rigidity.gif)
From this thread - http://www.countryplans.com/cgi-bin/yabb2/YaBB.pl?num=1171394000
Got Bracing?
(https://i35.photobucket.com/albums/d184/glennkangiser/bracing.jpg)
That was my first try. I'll do better on this one, promise. d*
...as long as you learn from your misteaks...
Quote from: glenn kangiser on April 21, 2008, 12:07:38 PM
...as long as you learn from your misteaks...
Didn't you mean
lean from your mistakes.
What was I thinking? hmm
glenn kangiser: I have a question about the comparitive rigidity of wall diagram you posted. Next to the 1/4" plywood sketch, on the right, it seems to say 4.2 nailed, and then 24.6 glued. Am I reading the 24.6 correctly, and how would one properly glue the plywood in order to achieve this high level of rigidity?
It's easy to joke around in these forums, but this is a sincere question looking for an educational answer.
Thanks in advance.
Sincere question, sincere reply. Construction adhesive, like Liquid Nails. Run a bead down each 2X, place the panel and secure with nails. If you do that to the corners you probably don't need to do every panel down each wall.
Nails 6 inches apart on edges of panel, 12 inches apart intermediate.
Ooops, I thought I was Glenn for a moment.... I must be [crz]
Thanks. I like it. I'm clearing old temporary storage from the cabin site. The excavator is coming as soon as things dry out a bit more. I'm actually started!
We just play when we're idling waiting for a serious question. If we're not kept occupied the ADD kicks in and we get lost.
You can be me while I'm out working, Don. After you're through with it I want it back. [crz]
Thought I would be home tonight so didn't take my computer. Here I am stuck in a motel 120 miles away. At least they have a courtesy computer. I'm hanging steel. Glad the question got taken care of by the very capable MtnDon. :)