Spray Foam Insulation
SPF (spray foam) is receiving greater recognition because of its ability to make homes more efficient. Like Cellulose, SPF is injected into the building cavities one bay at a time. SPF is a very effective air-barrier and is available in many different chemical make ups and R-values per inch. SPF also adds to the strength of the building by adhering to the many building surfaces and using it own rigidity. Widely known Icynene is a low density foam at R-3.6.
Several low density foams are offered in eco friendly formulas; soy-based, bio-polyols or even mushroom base. Many Icynene or polyurethane SPF’s are on the market; many have VOC’s (volatile organic compouind), CFS’s (chlorofluorocarbons) or HCFC’s (Hydrochlorofluorocarbons) within their chemical makeup; none is toxic, yet all are ozone depleting.
One of the highest insulation R-values achieved per inch is polyisocyanurate SPF (at R-7.6 its hard not to consider); yet the cost can be substantial. Spray foam offers many uses and options. Choosing the right product, its application, and the proper installer, are key components to a successful SPF investment.
Insulation R-Values Per Inch
|Fiberglass batts or blown
Icynene (low density spray foam)
Expanded Polystyrene (white)
Extruded Polystyrene (blue/pink)
Polyurethane (spray foam or board)
Polyisocyanurate (spray foam or board)
|2.4 – 3.0
3.3 – 4.0
3.6 – 4.2
5.8 – 6.8
5.6 – 7.6