One of the more heralded benefits of spray polyurethane foam is that it performs as an air and vapor retarder in addition to functioning as insulation. This is unparalleled in the insulation industry, as competing insulation materials like fiberglass and cellulose simply cannot deliver such additional performance characteristics.
In order to provide the same level of air and moisture blocking, fiberglass and cellulose insulation must be installed in conjunction with weatherization procedures. This involves sealing areas prone to air infiltration with sealants, often caulking. However, low-pressure spray foam works so well as an air and vapor retarder that it is often used instead of caulking to bolster the underperforming weatherization functionality of fiberglass and cellulose. With this in mind, Fomo produced a video overviewing the process of weatherizing a home with low-pressure polyurethane foam, utilizing both spray polyurethane foam (SPF) kits and one-component foam (OCF) sealants from cans.