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Should I Spray Foam My Crawl Space?

When considering whether to spray foam your crawl space, it's essential to weigh the pros and cons. Spray foam encapsulation is often chosen for its quick installation and low cost. However, there are significant drawbacks that homeowners should be aware of before making a decision. Understanding its effectiveness, potential issues, and alternative options will help you make an informed choice about the best way to protect and maintain your crawl space.

Spray Foam

New homes are being built everywhere, and many new homeowners are choosing to encapsulate their crawl spaces with spray foam. This process involves placing a liner on the ground and up the walls, then applying spray foam over the entire foundation wall. While this method is popular for its speed and low cost, there are significant disadvantages.

The theory behind using spray foam is that it helps regulate the temperature inside the crawl space by insulating the foundation walls, keeping the floors warmer in winter and cooler in summer. In reality, the main benefit of spray foam is that it seals gaps between the sill plate and foundation, as well as around HVAC or plumbing intrusions.

Moisture Spray Foam

Studies have shown that spray foam encapsulation is not effective at regulating crawl space temperature. During new home construction,  the ground is leveled, and dirt is built up against the foundation to create a slope, preventing water from entering the crawl space. This also provides insulation for the foundation walls so additional insulation won’t make much of a difference in the crawl space. 

Termite Damage in Spray Foam

Another major issue with spray foam encapsulation is that often it obscures the rim joists, making it impossible to detect termite damage. Termites can easily eat through the back of the spray foam, and their damage remains hidden until the foam is removed, giving homeowners a false sense of security.

Though spray foam encapsulation is cheap and easy, it is not the best option for protecting your crawl space from moisture.

Pooling Water

Spray foam insulation is typically provided by insulation companies, not waterproofing specialists, who may not fully understand the need for additional waterproofing measures. A professional waterproofing company, like The Crawlspace Ace, can identify potential issues that could lead to moisture and water intrusion. Along with our encapsulation methods, we offer solutions to prevent water from entering the crawl space in the first place.

Additionally, companies that use spray foam often do not include a dehumidifier in their encapsulation packages. If the crawl space is sealed with spray foam but lacks a dehumidifier, it can create stagnant, moist air. A dehumidifier is necessary to eliminate moisture buildup, which can cause mold growth and deterioration of wooden structures in your crawl space.

Encapsulation After Spray Foam Encapsulation

In conclusion, while spray foam encapsulation may seem like an attractive option, it is essential to consider its limitations and potential risks. Consulting with a professional waterproofing company can provide more effective solutions for maintaining a healthy and protected crawl space. Give us a call at (270) 556-7075 or fill out our contact form here, and we will do an on-site consultation to address the issues.

The Crawlspace Ace


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