I have done the rim joists in my basement using a similar spray foam product. The biggest recommendations I have are:
Use the kind of gun pictured and not the cans that come with a straw. It is much easier to apply consistently and you can actually stop work and start again the next day using the same can. The straws work OK but they always get clogged when you stop for a bit so only use them if you are working on a small area and plan on using the whole can in one go.
Look into the difference between closed cell and open cell foam. I’ve never seen closed cell come in a can like that so I’d bet money that is open cell foam. It works great for air sealing but you need to apply a ton of it to get an appreciable R-value. Closed cell foam is a lot more expensive in the spray form and is a 2 part mixture that is more complicated to work with.
What I ended up doing was buying some 2" closed cell foam board at the local hardware store. It’s relatively cheap in board form and is easy to cut. I cut a piece of the foam board to fit inside the rim joist space and then used the spray foam to air seal both the rim joists themselves and the small gap around the foam board. I think this is the most effective way to do it unless you go for the 2 part closed cell spray foam but that was more than triple the cost of the foam board + open cell spray foam.
For comparison, the 2" foam board has an R-value around 8 and, if memory serves, you would need something like 8" of open cell foam to provide that same level of insulation. You can get an equivalent R-value with 2" of the closed cell spray foam but last I checked the spray stuff was about $800 and an 8’x4’ sheet of 2" foam board is around $60.
The current bottle has been attached to my foam gun for well over a year. I only need a little bit every few months or so. After use I just close it and clean the tip. Previously I always removed the bottle and cleaned the gun after each use and they’ll stop working in less than 6 months.
This is the correct answer. Or use old school pink insulation.
One newer alternative my contractor used is timber hp, its physically like a block of firm tofu so you take the chunk/board and muscle it into the joists and it just stays. Its cool but cutting it looked miserable.
I have done the rim joists in my basement using a similar spray foam product. The biggest recommendations I have are:
Use the kind of gun pictured and not the cans that come with a straw. It is much easier to apply consistently and you can actually stop work and start again the next day using the same can. The straws work OK but they always get clogged when you stop for a bit so only use them if you are working on a small area and plan on using the whole can in one go.
Look into the difference between closed cell and open cell foam. I’ve never seen closed cell come in a can like that so I’d bet money that is open cell foam. It works great for air sealing but you need to apply a ton of it to get an appreciable R-value. Closed cell foam is a lot more expensive in the spray form and is a 2 part mixture that is more complicated to work with.
What I ended up doing was buying some 2" closed cell foam board at the local hardware store. It’s relatively cheap in board form and is easy to cut. I cut a piece of the foam board to fit inside the rim joist space and then used the spray foam to air seal both the rim joists themselves and the small gap around the foam board. I think this is the most effective way to do it unless you go for the 2 part closed cell spray foam but that was more than triple the cost of the foam board + open cell spray foam.
For comparison, the 2" foam board has an R-value around 8 and, if memory serves, you would need something like 8" of open cell foam to provide that same level of insulation. You can get an equivalent R-value with 2" of the closed cell spray foam but last I checked the spray stuff was about $800 and an 8’x4’ sheet of 2" foam board is around $60.
The current bottle has been attached to my foam gun for well over a year. I only need a little bit every few months or so. After use I just close it and clean the tip. Previously I always removed the bottle and cleaned the gun after each use and they’ll stop working in less than 6 months.
This is the correct answer. Or use old school pink insulation.
One newer alternative my contractor used is timber hp, its physically like a block of firm tofu so you take the chunk/board and muscle it into the joists and it just stays. Its cool but cutting it looked miserable.