Protecting a Richmond, VA Crawl Space from Moisture
Challenge
These homeowners in Richmond, Virginia, had moisture and mold issues within their crawl space. One of our experienced Home Performance Advisors was sent out to inspect the crawl space and propose a solution to any problems found. Our inspector first noticed that many of the insulation batts were falling from the floor joists (the crawl space ceiling). The fiberglass batts will absorb excess moisture like a sponge and eventually fall to the ground due to the extra weight. It was apparent to our inspector that there was a high relative humidity within this Richmond crawl space. Because of this high relative humidity, mold and mildew spores could be found along many of the wooden structures, including the floor joists. Mold will grow on any organic material, so long as there is a high relative humidity during warmer temperatures. Discovering the high amount of humidity caused us to look for a reason as to why that was, and we noticed that there were many gaps and tears within the existing vapor barrier, exposing the dirt floor of the crawl space. The gaps in this liner were allowing the earth's moisture to rise into the crawl space and affect the environment. Our inspector also noticed that there was a clear water line running along the foundation walls of the crawl space where water had been sitting. These porous cinderblock walls allow moisture to seep through them, and the open vents lining these walls allow the outside air and moisture to flow freely into the crawl space, raising the relative humidity. Our advisor wrote up their proposals and discussed possible solutions with the homeowner, and a decision was reached. The project work was scheduled, and the installers were sent out.
Solution
The first step during the project for our installers was to remove the old liner and any debris or trash left behind. Once the crawl space was empty, the installers applied an antimicrobial solution, called Shockwave, over the wooden floor joists to eliminate the mold growth. It is important to note that while the Shockwave will kill mold spores, it does not remove any staining left behind from the mold growth. The mold and mildew can grow back if the relative humidity and temperatures of the crawl space are not regulated or maintained. While we recommended applying insulation to the foundation walls, the homeowners of this crawl space decided to replace the insulation within the floor joists with 16-inch R-19 fiberglass batts. Once the insulation batts were installed, we used a 10-mil vapor barrier, called CleanSpace Light, to cover the dirt floor of the crawl space. This 7-layer polyethylene liner gets wrapped around all the piers, is sealed with a unique vinyl tape, and is attached to the foundation walls about six to eight inches above outside grade. This special vapor barrier will help to protect the crawl space from any moisture rising from the earth. Once the liner is installed, the installers create a foamboard block to fit into each open vent that lines the foundation walls. These foamboard pieces are sealed with can foam and will help to prevent any outside air and moisture from flowing into the crawl space. The final solution put into place by our installers was an Aprilaire E100 dehumidifier and a condensation pump. The Aprilaire dehumidifier will circulate dry air around the crawl space while regulating the relative humidity. Any moisture collected is then distributed to the condensation pump, which drains the water out of the crawl space via a hose line to a predetermined location on the property. Now that these solutions are in place, the homeowners can enjoy having a dry and clean crawl space under their home. If you or someone you know is interested in crawl space solutions, then please reach out to our company. We will help to keep the outside, outside!
