Thread: Ben's Garage
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Old 11-18-16, 06:39 AM   #29
DEnd
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Quote:
Originally Posted by bennelson View Post
I'm hoping to get some time soon to start the framing.

The whole south side of the garage is all doors - there's almost no structure there to hold the upstairs and the roof, so that's going to get a big fancy beam all the way across. I think that will be a fancy micro-lam beam special order from the lumberyard.
What are you doing for sheer on that wall? Yeah, yeah I know Wisconsin ain't gonna see earthquakes (ha!), you still need to ensure that wall has plenty of sheer strength.

That framing should go fairly quick. Even a couple of rank amateurs using small hammers should get the framing up in a weekend. Though I would hold off on putting up the trusses until you have time the next day to put on the roof sheathing. The trusses really aren't fully secure until the roof sheathing is on.

Also I noticed you will be using exterior insulation, and in-cavity insulation. For your climate I'm not sure 1/2" exterior insulation is enough (1/2" is barely adequate for my climate in NC). Especially considering the likely moisture load from running a vehicle inside, and the low temperature you plan on keeping the space. I'm not even sure the International Residential Code requirements are really enough (it's meant for houses with a higher indoor temp). The issue is really the low indoor temp and the in-cavity insulation as that will reduce the temp of the sheathing possibly allowing it to get to below the dew point. This will cause the sheathing to get wet, and wet sheathing is rotting sheathing.

*Late edit* The reason 1/2" exterior insulation is risky is not only does it not keep the sheating warm enough, but it also stops it from drying outward. Insulation, interior and exterior slows the energy flow by putting insulation on both sides the sheathing receives less energy to move the moisture out of it. Also the foam exterior insulation acts as a vapor barrier (almost completely eliminating vapor drive to the exterior as a way to dry out the sheathing).

Last edited by DEnd; 11-20-16 at 10:49 AM..
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