How Much Closed Cell Foam In Attic
Since closed cell foam has a higher r value per inch installers generally spray 2 in walls and 3 in rooflines to meet the energy code requirements of r 13 and r 19 respectively.
How much closed cell foam in attic. For an average 2 200 square foot home open cell foam insulation costs 1 254 for the minimum 1 5 thickness and 2 926 to spray the maximum 3 5 thickness on average while a closed cell foam installation costs 6 776. Cost to install spray foam insulation varies greatly by region and even by zip code. Enter your information into the spray foam insulation estimate calculator to determine how much foam you need for your project. This is more common with closed cell foam but it happens with open cell foam too.
Normally in occupied areas all spray foam must be covered by a 15 minute thermal barrier such as thick drywall per code requirements in irc section 316 4 and ibc section 2603 4. But anything over r60 is probably overkill and not cost effective if using closed cell foam only 10 worth if done in open cell foam you could get to code minimum with there with 11 and with another 5 6 of blown fiberglass for igintion barrier you d be at r60. Why spray foam insulation is so effective in meeting code requirements is that it has a higher r value per inch of product used than batts. Open cell foam installed 2 inches deep typically has a perm rating of around 15 while closed cell foam typically has a perm rating around 1 perm for the same depth.
However when we seal and insulate your attic deck using lapolla odorless open cell spray foam you re protecting that attic from tortuous high temperatures. 2 inch open cell spray foam insulation high. Invalid zip code find yours. 3 inch closed cell spray foam insulation get local cost.
The atlanta summer time attic is 130 140 degrees and i ve seen higher temperatures in tight restricted attics under certain conditions. Roof attic side open cell open cell 0 75 lb. There is 300 difference there but the cost they give you is about a third difference and open cell foam at 12 inches will not give you the performance of 2 inches of closed. Get free estimates from insulation contractors in your city.
Floor air seal closed cell 1 75 lb. The myth that open cell is more economical is bullshit. Closed cell spray foam r values. Spray foam insulation costs 1 36 to 2 63 per square foot depending on if it s open or closed cell.
Roof top side flat roof closed cell 2 5 lb. Closed cell 1 75 lb.