Q. Why does spray foam perform better than fiberglass?
A. Spray foam insulation’s air sealing properties are the primary reason for its superiority over fiberglass. Fiberglass, no matter how well it is installed, does not provide an air barrier and allows air to move through it. This allows the two climates (inside, conditioned air and outside, unconditioned air) to combine and create potential condensation inside walls and building assemblies.
Q. What is the difference between open-cell foam and closed-cell foam?
A. Both open-cell and closed-cell foam are great insulators. Both provide an excellent thermal barrier and air barrier. How they differ is that closed-cell foam is waterproof and will not let water move through it. Open-cell foam will allow water to move through it and dry. Insulation should not stop water. Roof, wall, and crawlspace assemblies are designed to keep water out. If water somehow does get into those assemblies, it needs to be able to dry out, especially in wood structures.
Q. Would I still need to ventilate my attic if I insulated it with spray foam?
A. No. Spray foam insulation is applied to the underside of the roof deck, raising the insulation plane from the ceiling to the roof deck. This creates a conditioned space in the attic area with typical temperatures in the 80° – 90° range instead of the normal 150°.
Q. In new construction, at what point in the building process do you install spray foam insulation?
A. You would spray foam at the same time as traditional fiberglass insulation, after passing mechanical and framing inspections and before hanging sheetrock.
Q. Is spray foam insulation better for sound attenuation than fiberglass insulation?
A. Yes. Spray foam has more density than fiberglass and its physical properties attenuate sound more effectively. Note: It is very difficult to specify how much sound will be reduced unless a specific sound wall assembly is designed (i.e. staggered stud, etc.).
Q. Does spray foam insulation require a larger investment than traditional fiberglass insulation?
A. Yes, there is a larger investment, but we have found that most of our customers are paid back the difference over a 3 to 5 year period through energy savings.
Q. Can spray foam insulation be installed in an existing home?
A. Yes, in the attic and around the rim joist to make your existing home more energy efficient.