Hey everyone! I'm working on my laundry room and I've hit a bit of a wall with my rim joist insulation. I've seen a few YouTube videos that gave me some ideas, but I'd love some advice or a second opinion before I dive in.
Here's the situation: I've got that typical gap between the foundation and the floor, and there's some old pink insulation along with various pipes in there. I want to seal off this area so I can finish the wall. My plan is to use foam board insulation, cut it to fit between the floor joists, and seal it up with spray foam. I'm also wondering if I need to add a piece of lumber to level it with the wall since I'll be installing PVC tiles on it. Is lumber necessary, or can I just make the foam board flush with the wall?
Also, regarding the spray foam, I'm trying to decide between the large 2-part box or just using the cans since it's just a few small areas I need to fill. Any tips on other methods to close off this area, steering clear of drop ceilings? Thanks in advance!
4 Answers
If you're just sealing around the edges of the foam board and pipes, you can totally get away with using the canned foam (like Great Stuff). It's fine for gaps no bigger than about 3-4 inches. No need to get the big two-part foam unless you're filling entire rim joist bays, which sounds unnecessary for you.
Are you planning to glue PVC directly to the concrete walls? If you're adding something like Chicago bars first, just extend that all the way up to the floor joists. Then you can finish your wall straight up from there!
I'd recommend going for the big 2-part foam box if you can handle it, but make sure to wear full PPE. You really don’t want to mess around with that stuff—it can be pretty hazardous!
Just spray foam the whole area. I used Dow Froth-Pak for a similar project and it worked great!
I actually plan on adding it right to the walls. I just need a little something at the top for insulation and to give the PVC something to stick to.