Full Encapsulation of an Unsealed Crawl Space in Disputanta, VA
Challenge
This Disputanta, VA homeowner asked The Drying Co./ThermalTec to come out and inspect their crawl space. They reported to us that there was a funny odor within their home and believed it to be coming up from their crawl space. We offered a free estimate and sent one of our trusted and experienced Home Performance Advisors to evaluate their concerns.
Once the home was inspected, we noticed mold and mildew growth on the crawl space floor joists. Mold is a clear sign of elevated relative humidity and temperatures within the crawl space. Organic material, such as the floor joists and the paper backing of fiberglass insulation, are an ideal food source for mold and mildew. The homeowners are noticing must and mildew odors in the home as a result.
A flimsy 6-mil vapor barrier, which feels like a large trash bag and rips easily, is covered in debris and fallen fiberglass. This liner is supposed to help seal off any moisture rising from the dirt floor. Instead, the liner is not completely sealed around the crawl space piers and foundation walls. There are gaps allowing the earth’s moisture to escape into the crawl space, increasing the relative humidity.
We then focus our attention on the foundation walls of the crawl space. They are porous cinderblock walls, meaning they allow outside moisture to leak in. Open vents line the foundation walls. The idea behind having vents on the foundation walls was to have the outside air to help to keep the crawl space dry. The reality is that moisture is simply entering and then settling within the crawl space. The outside influence will only cause your crawl space to be damp and musty during the warmer seasons and the floors of the first floor will be cold during the winter season.
The final problem lays with the crawl space entrance door. The door was made of wood and unsealed, allowing outside air and moisture to seep through the cracks. Rain, wind, and heat can often warp or even damage these doors, rendering them useless if the goal is to have a sealed off crawl space.
Once the inspection was finished and a free estimate was given to the homeowner, we worked together to discuss the best possible solutions for their crawl space. The homeowner accepted our project proposals and we sent out some of our skilled and talented installers to turn this dark and damp underbelly into a usable and sealed part of the home!
Solution
The first task our installers performed was the removal of all debris and trash, as well as the old 6-mil liner, from the crawl space. Then, our team applied Shockwave to all wood substructures, as it is a disinfectant and cleaner designed to kill mold spores. The installers spot-checked all floor joists, girders, and sill plates. The mold growth may have been dealt with for the time being, but without sealing the crawl space off from the outside there would be a chance for more growth to reoccur.
With the mold remedied we then proceeded to install a CleanSpace vapor barrier, a 20-mil 7-ply sandwich of high and low-density polyethylene with polyester-cord reinforcement, making it tear-resistant and treated with an antimicrobial finish that protects against mold and mildew growth on or under the liner. Moisture rising from the earth below will not penetrate this barrier. The CleanSpace is mechanically fastened six to eight inches above outside grade on the foundation wall.
The next step for the installers would be to seal the foundation walls to keep outside air and moisture from penetrating them. They use a closed-cell spray foam, which if sprayed at one and a half inches it acts as an air barrier and vapor retarder. The spray foam is applied over the CleanSpace while the open vents are covered with cut foam board and sealed with can foam. A 2-inch viewing strip is left for termite inspections.
A SaniDry Sedona is then installed into the crawl space to help control the relative humidity. The Sedona is a high-performance dehumidifier that helps regulate the total moisture within the crawl space air. The dehumidifier removes moisture from the air and drains it out of the crawl space using a Little Giant condensate pump. A hygrometer is given to the homeowners to monitor the temperature and relative humidity within the crawl space. We have exceptional technicians that will maintain and repair dehumidifiers for the homeowners.
Is your crawl space musty and damp? Do you have cold floors in the winter or smell funny odors during the summer? Then call The Drying Co./ThermalTec for a free estimate and inspection of your crawl space! Our friendly and expert employees and home performance advisors will be more than willing to help.
