Crawl spaces may not be a part of homes that are frequently inhabited, but they still serve essential functions. These narrow spaces under the home are a common alternative to a basement or concrete slab foundation and typically are used to conceal pipes and wires, or for personal storage purposes.
To keep these areas dry and free from excess moisture or pests, encapsulation is used to create a sealant. In this post, we take a look at crawl space encapsulation, how you can incorporate spray foam into the process, its benefits, and beyond. Keep reading to learn more!
The Importance of Crawl Space Encapsulation
Before hiring you for a big project, your customers will need to know about the value of encapsulating their crawl space. Here are the main benefits of taking on a project like this:
- Temperature barrier – Encapsulation creates a sealed environment which reduces temperature fluctuations and limits drafts
- Moisture prevention – Spray foam and vapor barriers work together to inhibit moisture, helping to prevent mold and mildew growth in the crawl space and keeping it cleaner
- Air quality improvement – By blocking external airflow, spray foam and a vapor barrier work together to improve indoor air quality, reducing the entry of pollutants and dust
- Odor control – Vapor barriers also create a smell barrier, preventing musty odors from the crawl space from entering a living area
Crawl Space Encapsulation Tips from SprayWorks Equipment
Contractors tackling crawl space encapsulation must pay careful attention to vapor barrier selection and spray foam installation techniques to ensure long-term moisture protection and structural integrity. The key considerations revolve around selecting the appropriate mil thickness for ground covering, determining precise wall coverage, and understanding proper sealing methods.
Our team of experts has supplied some detailed tips below.
Start with Vapor Barriers
Vapor barriers are a common way to prevent ground moisture evaporation from entering the crawl space air. Since these barriers help to resist the flow of air, your crawl space becomes semi-conditioned. The result? Temperatures in your home become similar to the ones in your crawl space, which means that your floors feel warmer in the winter.
For ground vapor barriers, industry professionals typically recommend using 12 to 20 mil reinforced liners, with the Viper crawl space liner emerging as a preferred product. Contractors emphasize avoiding standard polyethylene sheets, instead opting for specialized liners designed to block ground moisture and potential earth gases like radon. When installing these barriers, experts suggest running the liner 6-12 inches up foundation walls, ensuring complete coverage.
Best Practices for Crawl Space Encapsulation
Seam management is critical in successful encapsulation. Professionals recommend overlapping liner seams by 6 to 8 inches, using spray adhesive, and applying 4-inch vapor bond tape to create a robust seal. For block walls, contractors often extend the liner to the top of the first block course sitting on the footer, then spray foam over the entire surface for comprehensive coverage. This is one of the many reasons why using spray foam for crawl space encapsulation is helpful, as it adds a layer of further protection and insulation.
Additional best practices include addressing potential challenges like rocky ground surfaces. Some professionals suggest laying thin foam boards over uneven terrain or using inexpensive crawl space felt mats to create a smoother base before installing the vapor barrier. When dealing with potential radon or moisture issues, consider the use of a permanent vapor retarder instead of just a basic vapor barrier.
Insulation and Sealing Process
When it comes to encapsulating and sealing a crawl space, an efficient process is required. Proper installation involves several key steps: placing the liner, running it approximately 8 inches up block walls, nailing it in place, and starting spray foam application about 2 inches below the bottom plate.
This approach leaves a termite inspection strip while providing comprehensive moisture and gas protection. Contractors also recommend sealing any crawl space vents and ensuring complete coverage of foundations, rim joists, and walls. Using spray foam for crawl space encapsulation in addition to the vapor barrier completes the project by creating an extra barrier against external factors.
By following these techniques, professionals can create encapsulated crawl spaces that effectively manage moisture, prevent ground gas infiltration, and provide long-term protection for residential structures.
Using Spray Foam in Crawl Spaces After Encapsulation
It is very common to insulate crawl spaces once the encapsulation job is complete. In this case, we recommend using spray foam in the crawl space because it offers numerous benefits.
While the initial cost can be slightly higher for spray foam insulation when compared to other materials like fiberglass and foam board, it outshines the competition in areas like quality, damage resistance, and the actual encapsulation process. It also allows you to achieve a water-resistant seal that keeps your space warmer in the winter and cooler in the summer.
Let’s dive in a little further:
- Using spray foam for crawl space encapsulation in addition to the vapor barrier helps maintain a consistent temperature in the living space, saves energy, and reduces heating and cooling bills. Spray foam adheres tightly to surfaces, sealing both cracks and gaps that might be present, and keeps humidity steady as well.
- The lifespan of spray foam is greater than that of fiberglass bat insulation or foam board insulation, which can both slide or snag over time. Additionally, spray foam doesn’t collect dust or mold in the same way that traditional insulation is known to, reducing the need for maintenance. When using spray foam for crawl space encapsulation, homeowners can expect it to last between 80 to 100 years.
- It is important to emphasize that professionals should be the ones installing vapor barriers and spray foam in crawl spaces, as they have the proper knowledge and equipment. When not done correctly, vapor barriers and other materials can trap moisture against the wood and encourage mold growth. These results can negatively impact indoor air quality and health, which is why spray foam should be applied by trained professionals who use a reliable spray foam gun to complete the application process.
- If you’re a contractor who is looking to apply spray foam in crawl spaces, be sure to check out our spray foam kits. We are highlighting our HandiFoam® single- and double-component applicators, which are polyurethane spray foam dispensing systems. These are great for control over the amount of foam used, as the pressure you place on the trigger influences the amount of foam dispensed.
Start Applying Spray Foam in Crawl Spaces Today!
If your next gig involves installing crawl space encapsulation, SprayWorks Equipment has all of the resources you might need. Contact us to learn more about our equipment and training.
