On this page you’ll find everything you need to know about basement and crawl space water and moisture problems and solutions.
The problem with a dirt or vented concrete crawlspace is that as warm air rises in your home, it brings up with it the air that was previously in your crawl space, including moisture and mold spores, as well as anything else that may be airborne down there.
As this air rises in your home, replacement air enters from the lowest part, your crawlspace. This replacement air is made up with unconditioned outside air that enters through vents and other leaks, and air that is actually sucked from the crawlspace floor, either dirt or concrete, which is typically filled with lots of moisture. This natural upward air movement is called the “stack effect” — this is how chimneys work. Consequently, whatever is in the air at the lowest point eventually flows up into the living sections. Up to 60% of the air we breathe on the first floor of our home comes from the crawl space.
A concrete or dirt crawl space with a crawl space vents is a never-ending source of moisture. Even if the dirt’s surface seems dry, digging down a few inches reveals moist earth.
Because it’s moisture that leads to mold growth, musty odors, and structural damage. Also, insects and critters love moist environments. Poorly conditioned and moist environments lead to higher energy costs. Moisture ruins houses by providing a hospitable environment for mold, fungi, and insects that destroy wood framing. Crawl space moisture, and the mold and mildew that thrive in this environment, affect not only the floor system directly above, but also the entire house.
Three things destroy organic materials in general, and wood in particular: water, heat, and ultra-violet radiation. Of these, water is by far the most damaging… and is the one we can control.
Properly sealing the crawlspace and removing the moisture from the ground and air is part of the solution that helps provide a mold-free, radon-free, and insect-free environment, which leads to a more more energy efficient and healthier home.
To avoid moisture’s negative affects, a crawl space should be completely sealed and isolated from the ground and the humid outside air. An effective method to lower crawl space humidity, tested and perfected by CleanSpace, is a 7-layer plastic vapor barrier. This amazing product is now available in your area — the CleanSpace Crawlspace Encapsulation System by Basement Systems Inc.
The key to the CleanSpace system is the patented, 20-mil thick liner material. It’s a tough blend of seven polyethylene and polyester cord reinforcement layers, designed specially for crawl spaces. Since the side you see after installation is bright white, it really brightens a crawl space and lets you know that it is free of mold, insects, and dirt.
Plus, the CleanSpace liner is manufactured with an antimicrobial additive called Ultra Fresh, molded right into the material. The liner is so tough you can crawl on it and use your crawl space for storage without worry of putting holes or tears in it. And, of course, it completely stops moisture from getting in and ruining the underside of your house.
The CleanSpace Liner is tough enough for you to crawl on and use your crawl space for storage. Servicemen can crawl on it without worry of putting holes or tears in the liner. The liner completely stops moisture penetration. The CleanSpace liner is used to isolate the home from the earth completely and permanently.
Lower energy bills, resulting from reduced crawlspace humidity, translate into comfort and savings year after year. The CleanSpace crawlspace vapor barrier is tough enough for service people to crawl on and safe enough for storage. Being bright white, the CleanSpace liner really brightens a crawlspace too, making it a relatively pleasant storage place.
Many crawlspace foundations leak and many crawlspaces flood. Such crawlspaces may require a drainage system. Basement Systems has several patented sump pump systems for your peace of mind. They all feature a built-in WaterWatch sump pump alarm system to let you know if there is ever a pump or power problem before the crawlspace floods. Basement Systems’ SmartSump is a proprietary system that is unmatched in its reliability and function.
Just remember that your crawlspace, although often neglected until it’s too late, is one of the most important spaces in your home. It can be a spawning ground for mold, bugs, embarrassing odors, and even radon gas. The moisture generated in the crawlspace will lead to structural damage and higher energy costs!
On the other hand, a clean, sealed crawlspace can be an extra source for much needed storage while making your home more energy efficient, healthy, and safe for your family.
Mold spores, the seeds of mold, are in the air everywhere. All they need to grow is organic material such as wood, the right temperature range, and moisture. Of these, the only one that can be controlled is moisture.
Dirt crawl spaces often have the high humidity levels necessary for mold growth. Humidity levels from 50% to 90% are easily found in dirt crawl spaces that have never flooded.
Mold can grow on dirt, insulation, framing, and even under your carpet on the first floor. Mold destroys organic materials as it feeds on them. Mold reproduces by producing millions of floating airborne spores, which some people are very sensitive to. Spores can be dormant for many years, waiting for the right conditions to grow. Some molds produce mycotoxins, such as the black mold Stachybotrys. Many articles can be found on the effects of mold and toxic mold.
Don’t panic; there is a solution that will stop your crawl space from being a hospitable environment for mold. Mold will not grow when the humidity levels are reduced below 50%. Bay Area Moisture Control will make your crawl space inhospitable for mold.
Sealing the crawl space from the earth and outside air is the solution to moisture and dampness in the home. Some contractors and homeowners will simply put down a thin, non-UV-resistant plastic liner, like a 6-mil plastic liner.
This really has no effect as there’s still too much opportunity for air to enter from (air particles are very small) crawl space doors or hatches, crawl space vents, pipe penetrations, porous concrete walls, the hollow cores of blocks, and various other gaps and holes.
The CleanSpace crawl space encapsulation system includes solutions to all these challenges. It completely isolates your home from the earth. This dramatically reduces the humidity level in the air which, when combined with sealing outside air and dehumidification, will eliminate mold growth and rot from your crawl space and make the whole house healthier.
Our trained installers will remove wood and organic materials from your crawl space floor. Rocks and uneven surfaces are leveled, depending on the crawl space conditions. The CleanSpace liner is carefully cut and installed. Small holes are drilled into the top of your crawl space walls, and nylon fasteners are installed to permanently secure the CleanSpace liner to the walls.
The top edge of the CleanSpace liner is sealed to the walls with non-VOC sealant. All seams are sealed with special 4” wide sealing tape and/or sealant made for the CleanSpace liner. The result is an attractive, bright, tough, impervious liner – and a healthy home above it!
Sealing the outside air out and/or conditioning within the crawl space environment is the recommended solution. If insulating the crawl space is a concern, we recommend insulating the foundation walls with polystyrene insulation. You do not need to insulate the ceiling of the crawl space but check with your local building codes (because although they may not be optimal, or even based on the correct science, they are still the governing authority).
Insulating an Unventilated Crawl Space
According to the U.S. Department of Energy, the best approach to insulating an unventilated crawl space is to seal and insulate the foundation walls rather than the subfloor. In their consumer’s guide to energy efficiency and renewable energy, the advantages to insulating the crawl space are as follows:
The disadvantages of crawl space insulation include the following:
Of course we can’t create a vacuum in, nor ever be able to seal out all of the outside air from, the crawlspace, but the CleanSpace vapor barrier system comes as close as possible.
Sealing your crawl space is the first step. If sealing is not enough, then adding crawl space insulation is the next step. The cost of crawl space insulation pays for itself with its energy efficiency benefits. We will be glad to show you how insulating your crawl space doesn’t cost, it pays!
If you still have questions about basement and crawl space water and moisture problems and solutions, click here to download a PDF about the Crawl Space Encapsulation System.
