On the other hand, foam insulation has several advantages and is the best for crawl spaces because it creates a complete air seal or an air barrier.
Spray foam insulation does not absorb moisture, so there will be no issues of mold and mildew. Foam insulation also seals all cracks and crevices, and there is no possibility of shifting.
Foam insulation will last as long as your building structure is intact. Pests and rodents cannot enter your crawl space, and they will not be attracted to create their nest here because foam insulation is not a food source.
When installed correctly by a Top Notch professional, spray foam helps to complete the building envelope and conditioned air will stay in your home for longer periods of time. The R-value will range from R-3.5 to R-7 depending on whether you choose open-cell foam or closed-cell spray foam insulation.