Is spray foam insulation more effective than fiberglass batts?

Advantages of Spray Foam Insulation

Spray foam insulation offers superior thermal performance compared to fiberglass batts. It expands to fill gaps and crevices, reducing air leaks and heat transfer. This results in a higher R-value, with open-cell spray foam typically rating R-3.5 to R-4 per inch and closed-cell spray foam rating R-6 to R-7 per inch.

Disadvantages of Fiberglass Batts

Fiberglass batts, on the other hand, have an R-value of R-2.9 to R-3.8 per inch, but they can lose their effectiveness when cut or compressed during installation. They also provide a lower R-value when installed in wall cavities with high moisture levels or poor ventilation. This can lead to reduced insulation performance and increased energy bills.

Comparison in Fire-Resistant Applications

In fire-resistant applications, such as in commercial or industrial settings, phenolic insulation is often used. Phenolic insulation has a higher R-value (R-5 to R-7 per inch) and is more fire-resistant than both spray foam and fiberglass batts. It is ideal for areas where high temperatures and flames are a concern, such as in ducts, walls, or ceilings near heat sources.