Sealing a new Crawl Space in Williamsburg, VA

Challenge

This house in Williamsburg was recently constructed and the new homeowners wanted to encapsulate the crawl space. The homeowners relied on The Drying Co. once before, in an older home, and wanted to prevent future problems in their new crawl space before more costly repairs would be needed. The floor joists already had mold beginning to grow on the underside and fiberglass insulation was starting to hang down from the crawl space ceiling. Mold and mildew will feed off any organic material in the crawl space so long as there are warm temperatures and moisture in the air. Mold can cause health problems for homeowners and their families, such as musty odors, allergies, and even asthma. A standard 6-mil vapor barrier was used to cover the dirt floor and debris littered the top of the liner. This crawl space liner is easily ripped and there were many water puddles, which suggests that there was condensation from high relative humidity or water infiltration. Moisture in the air also caused the insulation in the floor joists to sag and fall out in certain places since water pulls apart the fine glass fibers on the insulation and makes it too heavy. Vents built into the foundation wall were letting outside air enter the crawl space, which would inevitably cause the homeowners issues. Cool winter air leaking in would cause higher heating costs and cold floors, while the hot summer air would bring moisture, increasing the relative humidity in the crawl space. The homeowners knew to act now before things got out of control and there were more costly repairs to make, and so they contacted us at The Drying Co., and we sent out one of our trusted home advisors to evaluate the crawl space.

Solution

The homeowners were given a free estimate and the crawl space was ready to undergo some major upgrades. First, we removed the existing 6mil vapor barrier as well as any debris. After the crawl space was cleared out, we supported any loose insulation hanging from the ceiling with 16” rods, because the fiberglass was not damaged, and the homeowners chose to keep it within the floors.

Then we physically wiped the underside of the floor joists and girders with Shockwave Antimicrobial to rid these floor joists of mold and mildew. It works as a disinfectant, sanitizer, and cleaner. Shockwave kills mold but does not remove the stains from wood floor joists. Mold and mildew will find it difficult to grow in a sealed crawl space so long as the relative humidity is controlled.

With the mold problem rectified, we then proceeded to install CleanSpace, a 20-mil vapor barrier, to all the floor sections overlapped and sealed with 4” vinyl tape. The liner was mechanically attached to the foundation walls 6” above the outside grade. The CleanSpace barrier comes with a 25-year warranty against rips and tears due to material failure. After the vapor barrier, we sealed all vents and penetrations in the foundation wall with foam, encapsulating the entire crawl space from the outside air.

Finally, we installed a SaniDry Sedona and condensation pump. The Sedona is a specialized crawl space dehumidifier, which filtrates the moisture from the air, keeping the relative humidity of the crawl space at approximately 55%, whereas mold will grow at above 60%. The homeowners were given a hygrometer, which will tell them the temperature and relative humidity of both the crawl space and their home. The crawl space is now sealed and protected from moisture and outside air, making it more energy-efficient for the homeowners!

If you wish to lower your energy bills and protect your crawl space from moisture and foundation damage, then contact The Drying Co./ThermalTec! Talk to any of our experienced team members to learn about our trusted and proven methods of making your home more energy-efficient and comfortable. Give us a call for a free estimate!