Choosing the Best Subfloor Insulation

When it comes to insulating the ceiling of your basement, crawl space, or elevated home, you have three choices: fiberglass, open cell, and closed cell. All insulation is not created equal, so which is best?

Best Insulation for crawl spaces and basements closed cell spray foam


You’ve likely heard that spray foams offer the best R-value per square inch, so it’s easy to assume that both open and closed cell offer the same benefits, but that’s a mistake that can lead to costly consequences.

All insulation is not created equal, especially when it comes to subfloors. Here’s why:

Although they’re both great insulators, open cell foam and fiberglass can trap moisture within floor systems in humid climates and flood prone areas, causing wood floors to cup, buckle, and stain. When applied to subfloors and crawlspaces, open cell is exposed to humidity, critters, and ground moisture. With these forces combined, long term trouble awaits and insulation efficiency suffers.

As the only insulation approved by FEMA, closed cell is the optimal choice to effectively insulate subfloors in flood zones. Not only is it waterproof, it also increases the strength of the building to which it is applied. As a vapor barrier, closed cell creates a seal that prevents humid air from moving through the insulation and into your home, keeping humidity and moisture out.

Before you start your next subfloor, basement, or crawl space project, contact the Energy One America team today for a prompt—AND FREE—estimate.

Energy One America Get A Free Quote
Energy One America Get A Free Quote


> Send us your info.

> We will contact you to schedule an appointment.

> An energy consultant will meet with you at your home.

> You will get a custom proposal with project description, additional options, and detailed costs.