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test
AGAIN
TEST
How to ______ down attic trusses to allow for 12 inches of insulation
please fill in the blank and then answer
fill in the blank
How to fur down attic trusses to allow for 12 inches of insulation
I am surprised the websie allows ...
ne to type 12 inches
ok, 10 inch
10 inch
Hey DoRight, Do you need to fur down just the slopes of the trusses or the ceiling as well. Can you simply hang new 2x4s off plywood gussets? I may be missing something here. I rarely encounter trusses in my line of work...
Thank you immensely.
Yes just the slope portion. So are you thinking, use 2x4s totally in-line with teh existing trusses and use plywood blocks nailed to both the new scab and the existing truss?
Thought of that. Might mess up insulation install a tiny bit (but only a tiny bit). I did not know if there was a good way to run furring perpendicular to the trusses to break the thermo bridging. Probably over thinking. And actually if I used your plan there would be a thermo break as well.
And if I cut all the plywood gussets perfectly and nail them on the scabs presisely I could push the plywood tight to the roof deck and get an easy perfect alignment of the 2 x 4 scabs without much fuss.
I have probably been over thinking the issue. I should have had the truss company add the scabs at the factory. Probably not cost much, been perfect and save alot of fussing. Something like that should almost be standard manufacturing practice for the trusss company. I am surprised more people don't ask for it. But then again most GC probably don't care about such things, and spec builders are looking to save every 50 bucks they can.
Sure thing DR, Yes that is what I was thinking. Plywood gussets nailed to the sides of the trusses so the new 2xs are in the same plane as the existing. You could just cut a bunch of 6" plywood rips to 15 1/2" long, flush one square cut with the top edge of the truss, then hang the new 2x off keeping it's bottom edge flush to the other square end of the gusset. That would be an easy way to keep everything straight-ish...
Fine
Would you and a helper take the time to verify that the trusses were true?
edit: experience has shown me that on occasion a single truss or more isn't quite the same in plane. It would be nice to know b/4 you in essence strap the truss and could correct the problem with ease. Has nothing to do with the walls they bear on.
Sure ..
Sure, if the trusses are screwed up then teh side walls would be messed up and you have another ball game.
Hey Calvin, I agree trusses can be pretty widely out. Even though they are built off jigs, the wood moves, twists, and the installation is rarely perfect too. For an unfinished space I wouldn't go crazy trying to straighten things out, but for any space big enough to be potentially finished someday then a little work to straighten would be well worth it. For a situation like DoRight's, we would probably set the 2 gable ends at the 12" space, then set everything between off strings top and bottom. We just finished the inside of a pre-fab shed that had trusses and found inches of variance particularly in the bottom chord height. We sistered every one before strapping the ceiling.
why did you specifically say
15 1/2 inches? Are you thinking I should want 15 1/2 inches o finsulation (less vent channel)?
HI DR, I was assuming the trusses are made up of 2 x 4"s, and if you wanted to add 12" of insulation, then the gussets would be 15 1/2" if you wanted to simply flush the ends of the gusset with the back edge of the exisiting truss and the front edge of the new 2x. Just a time saving idea to keep your tape measure in your pouch..
I am not adding 12 inches, but trying to get 12 inches in new contruction. So I would cut me plywood to 12 inches or whatever I need to give me one inch of vent and the thickness of R 38 bats. You can get high density R38 at, i think, 10.25 inches, so furring down 12 inche would give a 1.75 inch vent.
I think the plywood gussets is a great idea, and like you said, cut each gusset precisely and keep the tape in the pouch.