The crawl space has an integral role towards a home’s overall value as well as the living space above. Most homeowners in West Knoxville Knoxville don’t think twice about their crawl space unless they have to make repairs to plumbing, heating ducts or house wiring. While often thought of as no more than a storage area, it also has a tremendous impact on the overall indoor air quality of the entire home.
The Best Crawl Space Waterproofing In West Knoxville TN
By default, the air quality of a crawl space is typically poor. Mold, mildew, radon gas and poor energy efficiency all create several problems. The air that circulates within it eventually makes its way up through the living space. Scientific studies show that up to 50% of living space air originates from the lowest level of the home. With homeowners more concerned about their home’s indoor air quality, the encapsulating of crawl spaces has become a popular solution for such problems.
A damp crawl space creates a safe harbor for harmful molds, in addition to dust mites, termites and other bugs that can infest the home. The presence of excessive moisture will also create a serious problem with the probability for the wooden structure of a home to deteriorate. Crawl space vents pose a further problem. While believed to be a solution to moisture problems, they, unfortunately, make the problem worse. As it turns out, the vents allow cold air and moisture in, which rises into the living area and therefore decreases the heating efficiency of the entire home.
Another all-too-common problem associated with crawl spaces is radon gas. Though it cannot be seen, smelled or tasted, radon is a radioactive gas that can contribute to poor health, including cancer. Radon gas makes its way through the earth, into the crawl space and the home’s living space. According to the U.S.E.P.A., radon gas is the number one leading cause of lung cancer in non-smokers.
Ignoring these various conditions is not recommended for both long-term health and energy usage. Fully encapsulating a crawl space – by both sealing and insulating – is a fully efficient measure in addressing such problems. It makes sense to maintain and improve the lower level area in order to maximize healthy living conditions and home resale value.
While there are several systems for encapsulating, a zero perm liner system that also insulates and reflects heat provides the most benefits. With a proper floor and wall liner, the area will not only be well insulated but will seal out moisture, bug infestation, and radon gas. Other components to look for in a system include a radon gas-dispersing drain fabric, a radon gas ventilation pipe, and a ceiling heat shield.
A complete system with all of the above components will allow any soil gasses – including radon gas – that naturally occur under the liner system, to wick through the drain fabric and escape out through the ventilation pipe. While improved indoor air quality is the primary benefit of a sealed and insulated crawl space, the homeowner will also appreciate a bright, clean, and dry storage area; the ridding of musty smells; less energy usage; and tax credits. Contractors encapsulating crawl spaces will have more to offer to their clients when they can assure the peace of mind with improved indoor air quality.
A Closed, Sealed Crawlspace - What a Really Bad Idea
Outlined below are the most common 4 methods I have seen used in installing a vapor barrier. If you talk to different builders, you usually will end up with many different methods of installing a vapor barrier in a crawlspace. Here are the most common:
1. Pea Gravel on top of plastic vapor barrier - This has to be the all time dumbest thing I have ever seen, and yet it is probably one of the most common. I have had builders tell me that the plastic on the ground KEEPS ground water and moisture from coming up from the ground. Now if there is no moisture or water in the soil, this might be possible; but if that was the case there would be no need for the barrier in the first place. So here is the basic idea - ground floor (bottom) - plastic (middle) - 4" pea gravel fill (top). Once the crawl foundation is built, builders install a 4 - 6 mil plastic on the ground and dump about 4" - 6" of pea gravel on top of the plastic. Eventually, what always happens is that water comes in from the walls and the ground floor and ends up on top of the plastic. So what you end up with is a swimming pool liner that holds water in the gravel for prolonged periods of time. Nearly all the water and moisture in the gravel back fill has to evaporate into the structure. Another example of building practices and science turning a blind eye to crawlspaces for decades.
2. Vapor barrier on top of ground floor - By far the most common practice for installing a vapor barrier. A 6 mil polyethylene vapor barrier is placed over any ground floor. Here is the idea - ground floor (bottom) - plastic (top). The ground floor could be river rock, pea gravel, dirt floor, sand, etc. The seams are typically overlapped 6" - 12" and almost never taped. While this will temporarily stop some moisture evaporation, it does not seal out moisture from the internal perimeter wall where most water penetration occurs. Also moisture can come up from the seams, and the plastic is not durable enough to crawl on. It nearly always ends up with many punctures and holes in it.
3. Vapor barrier on bottom of floor joists - This is rarely seen, and usually only home owners attempt this. This is probably the method that accounts for more wood rot than any other method. If you are even thinking of doing this, quit thinking and call a professional to fix your crawlspace. Most crawlspaces are vented and the cooler surfaces such as duct work, pipes, and the floor will condensate in the summer. The plastic will trap the condensation up against the floor structure and mold and wood rot will occur. Good intentions do not always produce good results.
4. Vapor barrier fastened to sill plate - There is a new industry in crawlspace repair that encapsulates crawl spaces. The process of encapsulation is to install a heavy think plastic liner on the floor and up the foundation walls. The plastic liner is fastened and sealed to the foundation wall and all the overlapped seams are taped. Every potential gap or seam in the liner is meticulously sealed to prevent any moisture from evaporating. Then the vents are sealed in the encapsulation system to prevent hot humid air from entering in the summer. There is another system being sold and installed out there being represented as an encapsulation system, but is far from it.
This "other" system is a 6 mil plastic that is ran up the foundation walls and stapled to the sill plate. None of the overlapped seams are taped. It is basically a glorified vapor barrier on top of the ground floor being ran up the walls and stapled to the wood. They seal the vents without properly sealing the moisture from the ground floor or foundation walls. The problem with fastening plastic to the sill plate is that moisture will "wick" up the foundation wall, and moisture will absorb into the sill plate and floor joists. They are giving free access to all the moisture under the liner to rot the sill plates and floor joists. Not to mention that all the moisture will evaporate up through all of the seams that aren't taped and the plastic liner is only 6 mil and eventually will puncture and tear. Be very careful in the contractor you choose to properly encapsulate your crawlspace.
Thinking Long-Term Safety & Health With Proper Foundation Structural Repair & Basement Waterproofing
Many homeowners try to cut costs and increase their home's comfort level by installing a crawl space vapor barrier. This will instantly make your home healthier for you and your family, and prevent moisture damage, mold, mildew, foul smells and odors.
Most homeowners tend to look at their crawl space as separate space from their home, but in reality, the two are one. Water vapors that surface from the ground are continuously entering, creating undesirable conditions for you, your family, and your home.
The purpose of a crawl space vapor barrier is to stop moisture and wetness from entering and affecting the floor and walls of your basement. Moisture tends to flow from warmer to colder spaces.
Many homeowners don't realize the importance of the proper installation, in order to keep moisture and water vapors from getting in the walls and floor of your basement-- condensation can lead to expensive structural damage. Also, if you can help control the moisture and dampness, you can greatly reduce the amount of energy required to cool and heat your home.
When considering the installation of a vapor barrier, take into consideration two spaces in your home; the crawl space and the attic. Humidity tends to build in the walls of both these areas causing mold, mildew and dry rot. This can cause severe health issues for adults and children, especially for those with asthma, breathing difficulties, and allergies. In addition, it can cause severe structural damage to your home.
Some homeowners think that because they insulate the floor joists there is no need to do any additional work, but these items do not serve the same purpose!
Tips for Installation
One of the most popular do-it-yourself vapor barrier products is polyethylene, or plastic sheeting. This plastic sheeting comes in various thicknesses; 4mm, 6mm and 10mm.
With today's technology, this product is made from a high quality material, resistant to rips and punctures. Always check the soil so there aren't any objects or materials that may damage the lining. The slightest puncture, rip or tear could compromise the entire system.
Always, make sure the space is dry before you begin any repairs. To remove the moisture, you may need a dehumidifier.
Overlap the barrier a minimum of 12 inches on the side walls. Be sure it is tight. Use furring strips and masonry nails to firmly secure the lining then caulk along the joints.
Seal all the seams with a heavy duty tape. However, it is recommended not to use tapes that are not specially designed for sealing vapor barriers. When working in the basement you will be forced to contend with pipes, make the proper cuts and seal securely with tape.
The completion of your crawl space vapor barrier will be the best investment you can make in your home.
Crawl Space Masters Specializes In Crawl Space Encapsulation in West Knoxville TN.