[photopeter]

rigid foam board over interior studs

I am in the process of doing exactly what Michael76 described.
I don't understand why the screws could pop or the taped seems might separate.
The foam board will first be fastened to the 2x4 studs with nails that have a large plastic washer.
3" drywall screws will be used to fasten the 1/2" drywall boards through the 1 1/2" foam board into the studs on 16" centers (which will be marked on the floor).
Going right across the studs, rather than going in between, prevents thermal bridging by the studs and should be better than going in between.
I already have pink insulation between the studs right now.
I am removing the original vapor barrier covering the fiberglass insulation
before I will put the foam board on.

The electrical boxes are a bit of a problem, but there are a few options here, too.
An electrician told me I can just use longer #6-32 screws and mount the actual outlets (or switches) right against the drywall, leaving the box where it is. If the wire in the box has not been left long enough, pigtails can just get maretted onto them.
I don't like this too much, since I think over time the outlets and switches might wiggle loose rubbing on the drywall.

Since I work in a machine shop, I cut a small steel plate, the hight of the electrical box and about 4 1/2" long and riveted it to the side of an electrical box.
Now I can fasten this plate to the stud, bringing my box out to 1/2" proud of the foam board.
I thought another option could be by just fastening a 1 1/2" strip of wood on top of the stud where the box is mounted right now and just bringing the box forward to the proper depth.
Of course the foam board will have to be cleared for that.

Has anyone done something similar to this or see problems with it?
Michael 76, how did your job turn out?

 

[photopeter]

good idea

It makes perfect sense and sounds like a good and sturdy solution.
Thanks!