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Before: The fiberglass insulation in this crawl space is beginning to fall out of the floor joists, suggesting that there is an excessive amount of water being absorbed by the insulation, making it too heavy to stay in place. Fiberglass acts as a sponge and will pull in moisture from the surrounding air, but the water droplets will pull apart the fibers, and gravity will pull it down in heavy chunks. If the fiberglass has paper-backing, there is a good chance that mold growth will occur, for paper-backed insulation is considered “mold candy” for how easy it is for mold to thrive on it.
After: The crawl space walls have been insulated using Foamax foam board pieces, which are 1½ inches thick, and act as an air barrier and vapor retarder against outside influence. The open vents lining these foundation walls have also been covered on the inside using precisely cut foam board pieces and sealed with can foam. With the walls protected with Foamax, and the dirt floor covered with a 20-mil CleanSpace vapor barrier, outside moisture, and air will find it difficult to penetrate the underbelly of this home.
Before: The standard 6-mil vapor barrier shown in this crawl space is commonly found in Virginian crawl spaces but offers little-to-no usage when it comes to protecting the crawl from moisture damage. It is flimsy and easily torn by service people crawling on top of it while working. Holes form in this liner, and the dirt floor becomes exposed, allowing moisture from the earth to rise into the crawl space, increasing the relative humidity, and allowing puddles and mud to form. This creates a mess for homeowners and can allow mold and mildew to thrive on organic materials in this dark and damp environment.
After: A durable 20-mil vapor barrier, called CleanSpace, has been installed within this crawl space. It is a reinforced 7-layer polyethylene liner, much like a pool liner, which will protect the crawl space from moisture rising from the dirt flooring. The vapor barrier is finished with an antimicrobial, called UltraFresh, which will protect the liner from mold growth, although mold and mildew can still grow on any dust or dirt laying on top of the liner if the environment and relative humidity are not controlled. The CleanSpace gets wrapped around all piers and pillars and is fastened 6-8 inches above outside grade on the foundation walls, adding to the overall protection of outside air and moisture.
An interior, insulated, friction fit door is installed behind the existing crawl space door.
Spray Foam insulation is installed on the crawl space walls and the vents, rim & band, and sill plate are sealed and insulated.
The standard vapor barrier that is installed in the crawl space during construction is a flimsy 6-mil liner that is easily torn apart by any service persons, rodents, and pests who crawl on top of it. This ineffective vapor barrier does not get properly sealed around the piers or foundation walls. Moisture from the earth floor rises into the crawl space through these gaps, adding to the relative humidity if the temperature rises.
CleanSpace is a 20-mil thick vapor barrier that completely seals off the home from the earth’s moisture. It is wrapped around the piers and sealed to the foundation walls using a 4” wide vinyl tape. Moisture rising from the ground is not able to penetrate the CleanSpace liner, adding to the total control of relative humidity in the crawl space.