Crawl Space Waterproofing Bal Habor TN

The crawl space has an integral role towards a home’s overall value as well as the living space above. Most homeowners in Bal Habor Chattanooga  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.

crawlspace mold

The Best Crawl Space Encapsulation In Bal Habor 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.

mold in crawl space under house

Crawl Space Supports

There are advantages and disadvantages in having a crawl space under your home. Advantages, perhaps, a slightly elevated home may be more attractive than a home on a slab. Plus, you can make repairs and modifications to plumbing, heating, and electrical services.

Disadvantages, a crawl space is an area that is never cleaned. Under the vapor barrier the humidity is always 100% so mold and bacteria are always present. Termiticides, other chemicals, even rodent droppings may be present, and odors and gases that emanate will migrate into the home's living space unless proper ventilation is installed. Whether on a slab or elevated, if radon is present, good ventilation is required.

There are several technologies on the market in regard to moisture control. One is encapsulation, sealing the crawlspace. Though this might lower humidity, it's costly and there is no dilution or replacement of stagnant, poor quality air. Again, if radon is present, ventilation is required.

Another technology is to install a dehumidifier in the crawl space. This can lower humidity, but again will not dilute or replace the stagnant air. Another point to think about is that the dehumidifier will be costly to operate. More importantly, using a dehumidifier requires you to close tightly the crawl space. Thus, the home's living space air quality is going to be lowered because the crawl space air is not diluted and replaced with fresh outdoor air.

Some systems use a dehumidifier control (dehumidistat) to operate a crawl space vent fan. This sounds like it's going in the right direction. However, the technology isn't quite right. Here's why. Suppose the outdoor air is getting worse (wetter). Though the dehumidistat control is in the crawl space, it will quickly recognize this wetter air condition and begin ventilation, even though ventilating is going to make crawl space wetter. Another problem with a dehumidistat control is that most of them are not made for the difficult environment of a crawl space, so their warranties are short, 30 days to 1 year maximum for the dehumidistat.

There is another system that uses special technology different from all the others mentioned above. This special technology makes a comparison of the actual moisture content of both the air inside the crawlspace and the outdoor air. The result is that it pauses and does not ventilate when bringing in outdoor air is going to make the space wetter. Then, as the outdoor air is getting drier and is able to improve the moisture and air quality in the crawlspace, then this ventilator moves a lot of air which dilutes and replaces stagnant air, ultimately improving your home's living space air quality.

This system, called the Smartvent, is made in the USA, is used from Florida to Alaska... San Diego to Nova Scotia.

This system is a proven system, and it is the only system to have undergone a year long test where crawl space humidity averaged 46%. Besides the unique technology this system employs, it also has the longest warranty of all ventilators, five years.

crawl space conversion

What to Do About Basement Waterproofing Before It's Too Late

First, it might be quite costly (several thousands of dollars). Second, and much more importantly, the sealing of a crawlspace is likely to degrade the IAQ (Indoor Air Quality) in your living space.

Rather than sealing a crawl space and creating an IAQ problem in the home's living space, there are less expensive methods to manage crawl space humidity. In the United States, the number of those with allergies is rising about 25% per decade, and asthma cases alone have doubled in the last 20 years.

The rise in those having allergies is more common in developed countries, and it is suggested there "must be something in modern, urban life that promotes allergy". Some studies indicate a direct link to the increase in air conditioning and tighter homes. People may save a hundred dollars per year in energy, yet spend thousands on medication and life style change, so, there is no question that the home's IAQ is, by far, the overriding, single most important issue.

Proponents of sealing and not ventilating a crawl space have stated , "venting a crawl space will either add moisture to, or remove moisture from, a crawlspace depending on the moisture content of the ventilation air compared to the desired conditions of the crawl space. Venting with dry air reduces the moisture levels in the crawl space, while venting with moist air contributes moisture". In this respect, such proponents are absolutely right-on correct!

So, even though it might cost a homeowner $6000-$8000, they suggest a closed, sealed crawl space because the possibility of venting with moist air can make the crawl space wetter.

An optimum alternative that might achieve the best outcome could be to ventilate the crawl space but with a ventilation strategy that would know how much water vapor is in the outdoor air and know how much water vapor is in the crawl space air. Armed with that knowledge the ventilator will be able to make an informed decision whether or not ventilation is going to be helpful or hurtful.

It is evident a strategy like this would permit a crawl space to be ventilated, to dilute and replace stagnant air, odors and gases such as radon, yet not bring in wetter air into the crawl space. A strategy like this will be more effective than other ventilation strategies (like a timer or dehumidistat) because it is selective about not bringing in wetter outdoor air, whereas the timer or dehumidistat is not selective.

Returning to the question of sealing the crawl space and using a dehumidifier to control moisture, there is no question that sealing a crawl space and using a sizable dehumidifier will reduce humidity in the crawl space, but, if sealing the crawl space can compromise the home's IAQ, you ought to reconsider.

Here's why.

1. Even if you are able to seal the crawl space well, you will need a sizable dehumidifier. It will need to be set well below a mold threshold limit because other surfaces may be colder. The lower setting is needed to prevent those colder surfaces from exceeding the mold threshold in the now stagnant crawl space.

2. A dehumidifier mentioned in article requires 30 times the power of other technologies.

3. A dehumidifier will need occasional maintenance.

4. When sealing walls and piers, how do you seal completely without creating a hidden path for termites? It means, of course, you can't completely seal it.

5: The crawl space has become a stagnant area, which, of course, is never cleaned, so odors and gases will be there and they will migrate into the living space of the home.

6: Under the vapor barrier it is always 100% relative humidity, so mold and bacteria is going to grow. And the mold and bacteria spores will migrate into the home.

With the home IAQ in mind, it becomes apparent that some sort of ventilation is needed in a crawl space. The ICC code for the usual passive ventilation setup required one sqft of opening for each 150 sqft of crawl space. Further, the ICC code stated that if a vapor barrier was installed over the ground surface only 10% of the venting area was required (ICC 1804.6.3.1). This would mean that only 1 sqft of opening would be needed for a 1500sqft of crawl space. Clearly this code wasn't working, so the ventilation rate was arbitrarily increased, and, now, today some state codes recognize the strategy of comparing inside/outside water vapor.

So, with IAQ being so important, we can define our goal in a crawl space project: remove/replace stagnant crawl space air and extract moisture from the wood mass in the crawl space. This makes a case for mechanical equipment.

Dilution and replacement of crawl space air with fresh, outdoor air is easily understood, but how do you extract moisture from the wood mass in the crawl space? You must reduce the vapor pressure at the surface of the wood, and you may do this by either of two ways. One is by dehumidification, another is to blow air across the wood's surface, better yet, blow drier air across the wood's surface.

So let's get down to the quick of things. From the home's IAQ perspective you should ventilate your crawl space, but using a dehumidifier and venting would be like setting a dehumidifier out on your front lawn, and then paying the electric bills.

A better system would use an intelligent mechanical ventilation system that, (1) keeps the crawl space closed during unfavorable conditions, (2) opens whenever the outdoor air water vapor content will lower humidity in the crawl space, (3) moves a lot of the lower humidity air to extract moisture from the wood mass. The result is, that as you are diluting & replacing stagnant odors & gases, and radon in the crawl space with fresh, outdoor air, you are also extracting moisture from the wood mass.

Further, an intelligent system might perform other functions, such as to not ventilate when it's freezing outside, and, if the crawl space gets too dry, the ventilator could also automatically reverse its strategy to pump moisture into the crawl space to further stabilize wood floors by maintaining the wood in an acceptable range.

There is one inexpensive, automatic ventilator with all the characteristics described above. It's called the Smartvent®.


Crawl Space Masters Specializes In Crawl Space Encapsulation in Bal Habor TN.

http://crawlspacemasters.com/chattanooga/

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