Background:
I’m renovating a bedroom, and since I have to update the old two wire electric and make lots of holes for that, and since the “insulation” in this 80 year old house is… inadequate, I decided to just go down to studs and do things right. I’ve hung plenty of sheetrock in my day, but I’m not going to have a helper and dragging that stuff upstairs and fighting it alone I’ve decided isn’t worth it and so I’ll have a plasterer do it. It pains me, but sometimes writing a check is worth it.
Having finished the demo, what I had was 1/2 inch of 1940s sheetrock and then a full 1/2 inch of plaster. It was a shame to remove because it was a job well done. But this means that all my windows, doors, and cast iron baseboards are a full inch proud of the studs. And I’ll need to install the electrical boxes 1" proud as well.
Most modern plaster jobs are a skim coat on top of sheetrock. Of course I’ll ask the plasterer his opinions, but I’m wondering what the best option to make that inch is. As far as I know, 5/8 is the thickest standard size for sheetrock. So I could use two 1/2 inch layers, I could shim the studs, I could use one 5/8 and then ask for an extra thick plaster coat… Other ideas?
Just wondering what the collective wisdom of the Dope is on this matter.
I’m not a tradesman, so take my opinion with a grain of salt, but I’d think shimming the studs by a half inch or so would be the best option. That way you don’t have two layers of drywall, extra thick plaster, or anything else vaguely janky along those lines. Plus, it’s probably faster and cheaper as well, and isn’t as exacting as the other options would be.
I’d definitely discuss it with the plasterer; he may have an opinion about that as well.
I’d ask your contractor. First, he’s going to want to look at the studs and see if they need further work. 1/2" of plaster over your old drywall could hide a lot of imperfections from a poor framing job. So shimming may be necessary anyway. But depending on the cost of labor, a double thickness of 1/2" drywall may not be significantly higher in cost than other options.
Another possible option is to install 1/2" drywall over 1/2" foam insulation. This would increase insulation to exterior walls and add some sound proofing to interior walls. I think 1/2" of foam would be around the same price as 1/2" of drywall, possibly a little more, so it’s not worth it if you don’t want that additional insulation.
I’m also not a contractor, but I really like this idea - or at least, the idea of extra insulation and sound-proofing. Modern homes are so loud and echo-y - and I bet that’s a result of the thin drywall.
There are drywall products that provide more soundproofing than the common stuff.
I also remember seeing something where sheetrock was glued to foamboard and only secured with a minimal number of screws. The idea was it would prevent warping and cracking of the drywall from framing movement. Don’t know if that would make it worth doing.
ETA: Just looked at the price of soundproofing drywall. Costs can be 5 to 10 times regular drywall. 1" of foam and drywall combined at just twice the price is a way better deal when you need 1" altogether like the OP. Don’t know if sound insulating drywall is also thermally insulating on an exterior wall. Hardly worth the price if not.
Thanks for the thoughts. I too like the foam idea. The house has insulation, but it’s an old cellulose type (not blown-in) and in some places it’s turned to dust.
It’s a big old brick house and my heating bills can be quite high.
1/2" of foam doesn’t provide much in the way of sound or thermal insulation at all. I’m concerned that the foam might compromise the attachment of the drywall, resulting in nail/screw pops or cracking. The drywall installer may not warranty such a system. Where the cavities are opened up, I’d just use normal insulation, like fiberglass or cellulose batts. Then either shim the studs or do double drywall.