Homes built in the 50’s and 60’s often have crawl spaces rather than basements because they were less expensive to build. Those having crawl spaces with dirt floors have additional problems related to elevated humidity levels, including poor air quality, mold and mildew, dry rot, and structural damage.
Eventually, local building codes began to require that all dirt crawl spaces be built with vents and a vapor barrier over the floor. A vapor barrier is a piece of polyethylene plastic that is sealed with tape at the edges of the crawl space. It is designed to keep ground moisture out of the crawl space. Often installing a vapor barrier is not enough, and scientists recommended crawl space encapsulation as the best solution.
Sometimes simply installing vents and a vapor barrier over a dirt crawl space doesn’t solve all of the problems. Buildings may continue to have issues with mold and mildew, dry rot, and structural damage. Scientists discovered ground moisture was not the only source of moisture. Water continues to seep through the concrete block walls and crawl space vents. Especially during the summer months, the vapor barrier and vents make the humidity problem even worse.
Because of the difference in temperature between the crawl space and outside air on warm summer days, the relative humidity inside increases by 20 percent for each 10-degree temperature difference between the inside and outside. In other words, if the outside temperature rises to 80 degrees, while the inside temperature remains 70 degrees, there is a 20 rise in relative humidity levels. At 90 degrees, the difference is 40 percent.
Whenever the relative humidity levels within the crawl space rise above 65 percent, mold and mildew begin to develop. The continued growth of mold and mildew eventually weakens the structural integrity of the home. In addition, it negatively affects the air quality inside the home. The high humidity also decreases the energy efficiency of your home.
A number of reputable organizations, including Advanced Energy, Habitat for Humanity, and Building Science Corp, studied the crawl space humidity problems and concluded that the best way to treat crawl spaces in either new or old construction was to implement crawl space encapsulation. Today’s building scientists have proven that crawl space encapsulation controls both moisture and overall air quality. They also discovered it improved a home’s overall energy efficiency by 10 to 20 percent.
Crawl Space Encapsulation involves three primary steps:
While it is relatively easy to put plastic over a dirt floor, complete crawl space encapsulation with proper venting and air conditioning is something only an expert can do. At Basement Masters Waterproofing, we specialize in dirt floor crawl space encapsulation projects in order to prevent mold and mildew, ensure good air quality for your family, and keep your home energy efficient. Contact us today!