Bringing gussets down to line up with knee all in attic
With help from this forum, I now have a way of tackling bowed rafters in an attic I’m getting ready to renovate. The 2×6 rafters are not deep enough for the closed spray foam insulation I plan to add, and are so bowed that they will present a challenge for hanging drywall.
The solution developed here is to sister plywood gussets to the existing rafters and then attach 2x3s to the gussets. Depending on the rafter, I’m cutting the plywood 6-8 inches wide and two feet long, and attaching to the rafters with #8 2 inch construction screws. I’ll then screw the 2x3s to the gussets to get an even surface for the drywall.
I’ve run my string lines and am attaching photos of the lower most string line, which runs right along the attic knee wall I installed.
My question is this: any recommendations on how best to cut and attach the lower most gusset so that it meets the knee wall correctly? Clearly I need to cut all the gussets on the same angle, but how do I position them so that they all meet knee wall at the correct place, and in such a way that I won’t run into problems when I hang the drywall?
In the last two photos, I placed 1/2 plywood up against the knee wall where it meets the rafter, imitating what the drywall will do when I hang it. I’m tempted to screw in the plywood temporarily and use it as a backing for the gussets, but I worry that while I can take it out, I’m not sure I can slide the drywall up in its place after the gussets are screwed in.
Thanks in advance for any tips on how to handle this.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
Would you be able to leave the plywood in place? Maybe rip the plywood so that it only hangs on the knee wall to the depth of the new gussets. It looks like the roof framing and knee wall framing don't line up with each other, The plywood would help secure the bottom of the gusset/2x3 nailer. The new drywall could then butt up to the plywood.
If you use 5/8" drywall on the wall, you could span that small gap without backing and you should be OK. That's what I did in a similar situation.
Bill
You hang your lid first. I don’t really see the issue. Also attach your gussets to you 2x3 first and hang as a unit. Also use no coat bead for your off angle transition.
To elaborate a bit on how I handled this same situation in my own home, I hung the 1/2" lid, then just let the 5/8" wall drywall span up to the lid and taped/mudded in the usual way. The unsupported edge of the 5/8" drywall is only maybe 1" or so, so not really a problem. Doing it this way is a lot easier than trying to cut a bunch of angled pieces of wood to back up the drywall joint.
Bill
Yes this I pretty common, especially when your birds mouth does not equal your top plate. I would definitely suggest 5/8” for the lid though. No coat bead give you a perfectly straight line and is much stronger than tape