How Much Closed Cell Foam In Attic
Open cell foam weighs 1 2 pound per cubic foot and closed cell weighs 2 lbs per cubic foot.
How much closed cell foam in attic. 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. Closed cell spray foam r values. Roof attic side open cell open cell 0 75 lb. Enter your information into the spray foam insulation estimate calculator to determine how much foam you need for your project.
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. Closed cell 1 75 lb. 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.
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. Get free estimates from insulation contractors in your city. 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. Floor air seal closed cell 1 75 lb.
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. 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. The myth that open cell is more economical is bullshit. For example closed cell spray foam depending on brand can offer an r 6 or r 7 per inch.
Intumescent coatings are not always needed to coat spray foam in the attic in order to meet code thermal barrier requirements. The atlanta summer time attic is 130 140 degrees and i ve seen higher temperatures in tight restricted attics under certain conditions. Roof top side flat roof closed cell 2 5 lb. 2 inch open cell spray foam insulation high.
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. Spray foam insulation costs 1 36 to 2 63 per square foot depending on if it s open or closed cell.