Colder climate zones present even greater opportunities for SPF market growth. The inside-to-outside vapor drive and chilly winter temperatures set the conditions for condensation on vulnerable surfaces such as roof decks.
The building code prevents condensation within the roof deck by specifying closed-cell foam. However, on a material cost basis, closed-cell foam costs 350% more than equivalent R-value of open-cell foam. Since the benefits of closed-cell foam occur in the first few inches, adding foam to reach high R-values amounts to an uneconomical use of material. Hybrid attic assemblies with closed-cell and open-cell foam ameliorate the situation by reducing
the material cost by up to 30%. The cost premium associated with any closed-cell foam system discourages builders from adopting unvented attics with SPF in colder climates.
Alternatively, preventing the movement of water vapor into the attic assembly with a class II vapor retarder economically expands the use of open-cell foam in cold climates. This two-step solution makes SPF more accessible to an entirely new market of builders. Reaching an R-60 with closed-cell foam
requires nearly 8½-inches of foam. The material cost alone to insulate 1,000 sq ft of roofline is approximately $4,250. The material cost for a high yield open-cell foam at 16-inches averages around $1,200-$1,300. This dramatic difference leaves abundant room to cover the added costs for the application of a vapor retarder coating.
Read Full Article From SPRAYFOAM PROFESSIONAL, SPFA, Winter 2024
By No-Burn, Inc.