Full Crawl Space Sealing in Smithfield, VA
Challenge
This homeowner in Smithfield, VA called us at The Drying Company to discuss moisture problems within their crawl space. We sent out one of our trusted and professional Home Performance Advisors to evaluate their crawl space situation and provide them with a free estimate.
The first thing we noticed upon arrival was the amount of fiberglass and debris littering the floor. The fiberglass insulation sits in the floor joists under the subfloor in the crawl space, providing insulation to the first floor of the home. However, excessive moisture in the crawl will cause the fiberglass to act as a sponge, sucking it up. The moisture pulls apart the fine glass fibers and adds weight to the fiberglass, causing it to delaminate and fall to the floor in chunks, rendering it useless.
Underneath all the debris and insulation is a 6-mil vapor barrier full of holes and tears. This is the only thing covering the dirt flooring of the crawl space. The Earth’s moisture can freely rise into the crawl space through the holes, punctures, and tears of this flimsy liner. This will increase the relative humidity, which can lead to mold growth or condensation. Termites, pests, and critters also love this damp and dark environment.
The next thing we noticed was the efflorescence forming on the foundation walls of the crawl space. Efflorescence is a white, powdery chalklike substance residing on the surface of the cinderblock wall. This occurs when outside moisture forces its way through these porous cinderblock walls, bringing all the salts and sediments to the surface.
The open vents lining the walls also allow air and moisture to affect the crawl space environment. The idea behind the vents was to allow them to remain open during warmer seasons, allowing the outside to dry out and ventilate the crawl space while closing the vents during the cooler seasons to keep the home’s floors from becoming too cold. The problem is that the air and moisture from the outside becomes trapped in the crawl space, which adds to the relative humidity of the space.
The final thing we addressed was the crawl space entrance itself. The crawl space door was made of wood and is at the mercy of the elements, which will fade, warp, and rot it. The cracks between the door itself and the foundation wall are also allowing outside air and moisture to seep through, as well as pests and small critters. All these issues are allowing moisture to dominate the crawl space environment, affecting the air quality in the home, and the relative humidity in the crawl, itself.
Solution
We began by clearing out the crawl space of all debris, items, loose fiberglass, and the old vapor barrier. Then our installers installed a custom 20-mil vapor barrier called CleanSpace. CleanSpace is a heavy-duty liner, much like a pool liner, that covers the dirt flooring of the crawl space, protecting the area from the moisture rising out of the earth. The vapor barrier also comes with an antimicrobial, called UltraFresh, built into the material to help prevent mold or mildew from growing on the liner itself. It is wrapped around all the piers and mechanically fastened to the foundation walls six to eight inches above outside grade. The white CleanSpace liner keeps the crawl space looking clean and bright.
The next step was to cover the open vents lining the foundation walls, as they were allowing outside air and moisture to freely flow through the crawl space. Precisely cut foamboard pieces were inserted into the interior of these vents and sealed with can foam. The rim band and sill plate were also sealed with foam to stop air and moisture infiltration.
Then we needed to insulate the porous foundation walls, as well as the open vents. We used 1½ inches of closed-cell spray foam to cover the crawl space walls. This thickness of spray foam acts as an air barrier and moisture retarder, giving better protection to the crawl space from outside influence. The complete system can help to improve indoor air quality, energy bills, and keep floors warmer in the winter.
A Sedona SaniDry was added to regulate the relative humidity in the area. This energy-efficient dehumidifier circulates dry air throughout the crawl space by pulling the excess moisture out of the air, keeping the relative humidity below 60%, where mold and mildew growth begins.
With this solution in place, the homeowners have peace of mind that their home’s foundation is protected. If you or someone you know has a wet crawl space, then call us at The Drying Company for a free inspection and estimate. We will help you and your family to keep the outside, outside.
