Invasion of the Insulators

Meet Jamie and Armin, installers of “close cell” foam. I wanted 4 inches of foam, they suggested 3.3 inches and I think they ultimately sprayed 4.5 inches of this foam gives us an insulation value of R28. Add that to the exterior sheathing and the already installed three quarters of an inch of exterior Styrofoam Cladmate and we should be close to R32 or better on the wall insulation. The SIP, Structural Insulated Panel roof with 9.5 inches should be around R66 and add the ICF Insulating Concrete Foundation blocks with 5 inches of closed cell with an R35 and all I can say is that this house is now super insulated.

Closed cell spray foam is also referred to as 2 pound or medium density. This foam expands 20 to 30 times its liquid size, and seldom requires trimming with little to no waste. Closed Cell foam cures rigid and the millions of microscopic bubbles which form during the expansion reaction remain closed and intact. This traps the reaction gases, and as such the R-Value of Closed Cell foam is close to that of the reaction gas, around R 7 per inch. The Closed Cell structure is very strong; increasing shear and racking strength by 300%. Closed Cell foam is a Code Approved Vapour Barrier with a permeability rating of under 45 ng, as well as a Code Approved Air Barrier and Thermal Insulation. Closed Cell foam is spray applied as a liquid to create an air-tight seal as it expands as a foam to stop air leakage. But unlike Open Cell foam, Closed Cell foam stops both convection through and within the wall cavity. Conservation is always the best form of energy savings so I can now say that I am extremely happy with this part of the construction.