Spray foam insulation - PA installer
- Thread starter Chester11
- Start date
I wouldn't do it. The substrate and the chemicals have minimum temps which are difficult to hit in the winter. Cellulous under your floor (above garage ceiling) would probably be cheaper and you can do it now. The other issue is the air leaks at the kneewalls (I'm assuming your office is a truss cavity and cold air getting underneath the floor from the sides.
Surface mount only.
The OP needs to wait until summer to do this.
Thanks - I think you hit the problem. I had rockwool installed in the garage ceiling a few years back. It's didn't make much of a difference unfortunately.
I was thinking spray foam to seal the knee wall and overhang, but wanted to talk to someone before I wasted a bunch more money.
You could probably install the blocking yourself yourself by cutting pieces of foam and using SPF kit to set it. I work in a third floor poorly finished attic and I can sometimes feel drafts coming in from bottom of the walls. Right now I'm almost sweating because we had to convert the space into one large by-pass damper for our zoned system.
I really want to learn all things insulation, I would love to insulate my garage properly, and if I can actually understand and learn about home insulation. I would definitely invest in that for the long term, you can save a lot on utility bills.
I think I would buy one of those radiant heat dishes and aim it at myself.
cost less than 7cents an hour for me on low.. and high will melt you out of your chair at 5ft.
cost less than 7cents an hour for me on low.. and high will melt you out of your chair at 5ft.
Sorry what's SPF kit? (My google searches return sunscreen).
Last time I tried to build a foam "cover" for my attic access it was a disaster. The adhesive I used wouldn't stick, and ended up using metal duct work tape. (I later learned that using the wrong glue could melt the foam). It was a mess - wife was pissed foam shavings everywhere. I measured wrong, and couldn't figure out how to cut the foam. (I had to cut it in the home depot isle just to get it home). So my insulation DIY game is sadly limited, to say the least.
It’s quite common up here. You want the “closed cell” foam. There are various brands and many of them contain a purple dye. The magic of foam is that it is around R-7 per inch compared to R3-R3.5 for fibreglass pink insulation. It’s quite popular in older homes with 2 x 4 studs and either wood chip insulation (R1 per inch) or no insulation whatsoever. Typically contractors strip off the inside dry wall, and spray 3” in the cavity resulting in R21. You don’t want to overfill or else you’ll be carving off foam to be able to put new drywall in.
It also provides a vapour barrier. No need to add plastic. Also, It has no connection to the urea formaldehyde stuff of the 70’s which was a disaster.
Another very popular place for it is in the header area. The main part of the walls is done with fibreglass pink or Rock Wool and then the spray contractor comes in and sprays the header area in the basement. In your case you have a header where your flooring joists rest on the main floor walls of the garage. That area is usually subject to poor insulation. Google header in wall construction.
It also provides a vapour barrier. No need to add plastic. Also, It has no connection to the urea formaldehyde stuff of the 70’s which was a disaster.
Another very popular place for it is in the header area. The main part of the walls is done with fibreglass pink or Rock Wool and then the spray contractor comes in and sprays the header area in the basement. In your case you have a header where your flooring joists rest on the main floor walls of the garage. That area is usually subject to poor insulation. Google header in wall construction.
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Looks like the new model is 1000w only? oops.
In a living space, I would not use foam. Too many variables, specially when it comes to mixing the chemicals, if the installer gets the mix wrong, it will be a disaster and can even be dangerous to occupant health.
Use fiberglass bats and blown in insulation. These are proven and have no health or air quality risks.
Use fiberglass bats and blown in insulation. These are proven and have no health or air quality risks.
Yeah - I had read that some installers could botch the mix, and that it off-gases while it cures. (I watch a bit of Mike Holmes, and it seems popular in Canada). That was the reason I held off the first time - plus is was cold, and the contractor fit me in.
Now I am facing having to reopen the garage ceiling again or tearing into drywall in my office. (It's an add a room over the garage, and just really poorly constructed.) Talking it through here, it sounds like going from the office out into the overhang is the best plan.
If you like, do a quick sketch of what you have. It could be that you are just not sending enough heat up to your office. I recommend those free standing oil filled electric heaters that don’t require fans. In any case, a plan view and side view rough sketch would help.
You can buy a spray foam kit at HD, Lowes, Grainger, etc.. Just cut the rigid foam to match the floor joist spacing and tack it in with the spray foam. Otherwise you gotta pile up the insulation above the depth of the floor joist
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Thanks...appreciate it.
I had a heat pump installed a few years back and it made a big difference, but the floor is still cold in January / Feb.
