BASEMENT AIR QUALITY

Do you smell mildew in your finished basement?

You just spent all that money to create a finished basement to enjoy and entertain in and now it smells like an old sneaker.

Sound familiar?

Many homeowners who have finished basements soon discover that unchecked moisture and humidity soon lead to foul smelling mildew. Mold and mildew will flourish in areas of your finished basement that are damp, poorly lighted, warm and have weak air circulation.

Mildew is actually produced by molds when there is adequate moisture supply and warm temperatures. Mildew feeds on cellulose material and emits volatile organic compounds (VOC's) that produce the nasty smell associated with damp basements. Mildew will feed and grow on a variety of surfaces in a finished basement

Homeowners with basement moisture problems sometimes debate whether the solution is an air conditioner or a dehumidifier. Both instruments operate on the same fundamental principles so it can be easy to become confused. The major difference is that air conditioners cool the air, but they remove very little moisture from it. When air passes over the air conditioners coils, it becomes cooler and a little moisture is removed as a side effect. Dehumidifiers are designed to take the water out of the air. When moist air passes through the dehumidifiers evaporation coils it falls into a collection bucket or is expelled through a drain hose. You can run an air conditioner and get the temperature down so low you could hang meat in your basement. However, your walls would likely be covered in water.

Mildew is actually produced by molds when there is adequate moisture supply and warm temperatures. Mildew feeds on cellulose material and emits volatile organic compounds (VOC"s) that produce the nasty smell associated with damp basements. Mildew will feed and grow on a variety of surfaces in a finished basement:

  • Carpets
  • Draperies
  • Furniture
  • Wood paneling
  • Paper products
  • Garments made from cotton, leather, silk, wool and linen

Damp basements are often caused by condensation of moist, warm air on cooler interior wall and floor surfaces. Wet walls and foggy windows are good indicators of high levels of humidity. The first step to eliminating mold, mildew and musty odors in a finished basement is to dry the air and exhaust the air.

Left untreated, mildew can cause considerable damage to your valuable property and to your finished basement. Remember, mildew and molds are much more difficult to remove than they are to prevent.

Relative humidity is a percentage that tells you how much moisture is in the air relative to the maximum amount the air can hold at that temperature. For example, when air at a given temperature contains all the water vapor it can hold at that temperature, the relative humidity is 100 per cent. If the humidity is higher than 100 per cent, moisture will begin to condense from the air. If the air contains only half the water it can hold at that temperature, the relative humidity is 50 per cent. Warm air can hold more moisture than cool air. The relative humidity of a sample of air will change as the temperature changes, even though the actual amount of moisture in the sample air does not. For instance, as a sample of air cools, the relative humidity rises. Generally, the right moisture level, the relative humidity in your house is less than 50%. Having a basement not being cool enough is usually not an issue. Basement temperatures tend to be cool because of the nature of basement construction.

Damp Basements Are an Invitation for Mold

Basement Mold Will Grow Even If There Have Never Been Flooding or Leaks.

Many people associate mold in basements with flooding. Although flooding, leaky pipes, leaky roofs and clogged gutters are certainly contributors to mold growth, many times the main culprit is excessive basement humidity. Regardless the air temperature, there will always be cold concrete floors and wall materials that take on the ground temperature of the soil around your home. A damp basement can provide an inviting environment for mold growth. Mold grows the fastest in your basement when there is lots of moisture. It can grow on many surfaces, including walls, floors, carpets, ceiling tile, wallpaper and insulation. 

  • Have you ever opened the basement door and noticed the musty smell of your basement even though it looks completely clean?
  • No matter how much you vacuum floors and clean surfaces, do you find that the odor is still there?

The most common place for mold growth is beneath carpet, behind drywall and behind insulation. Basement mold grows directly on the concrete floor, cinder block, brick or concrete walls and beneath pipe insulation.

Molds are microscopic organisms that are a type of fungi. There are over 100, 00 species of mold and mold spores are so minute that as many as 250,000 can fit onto the head of a pin! Besides negatively affecting your health, molds can damage your home. They can eat through basement insulation, wood framing, carpeting and other organic matter. When molds eat this organic matter they emit volatile organic compounds (VOC's) that contribute to poor air quality.

You can usually detect mold in your basement by smell or sight. Spots on walls, floors and carpets are indications of mold infestation. Molds produce a highly noticeable damp, musty odor that in extreme cases can be overpowering. Peeling paint and stained wallpaper are other indicators of mold growth. Many homeowners make the mistake of painting over mold. Out of site out of mind doesn't apply here. Painting over mold is a poor mold remediation solution because mold will feed on the paint itself.

If you do have mold in your basement don't feel alone. The American Society of Home Inspectors estimates that 60% of U.S. homes have wet basements. Even well built and sealed basements that would not have mold under normal circumstances can develop mold growth from high humidity. Many basements feature concrete walls and floors. Unfortunately, concrete is a porous substance that can trap moisture and provide a home for mold growth. Wet basement walls and floors are usually signs of condensation caused by high humidity.

The optimal humidity level in your basement should be below 50%.

Basements - Allergy and Asthma Symptoms

One out of every five people in the United States suffers from allergies?

There are several causes of allergy symptoms: food allergies (peanuts/dairy), seasonal allergies (pollen, mold) and pet allergies (dander).

A vast number of homes with basements have moisture problems. Humid, damp basements provide the perfect environment for mold and dust mites that could be causing or exacerbating your allergy symptoms. These two irritants cause the vast majority of airborne allergy symptoms. In fact, studies show that nearly all chronic sinus infections are a result of mold. If you suffer from allergies, you know the symptoms: sneezing, congestion, headache, heavy mucus discharge, inflammation of the mucus membrane in the nose and sinus.

For those of you who don't have allergies, the term refers to the immune systems over-sensitive response to bodily contact with a particular foreign substance (mold, dust mites). The symptoms of mold allergies are similar to those of other allergies.

Basement Mold Contributions to Allergy

Mold spores, like pollens, are airborne allergens that are easily carried by air currents. Mold is a fungus that reproduces by releasing vast numbers of spores into the air. For some individuals, inhaling mold spores can cause an allergic reaction. Even hay fever symptoms can be caused by deposits of mold spores on the lining of the nose. The most dangerous of all basement molds is Stachybotris chartarum, better known as black mold. Black mold is suspected of being a contributing factor in allergies and asthma.

Dust Mite Allergen

The other culprit in making your allergy symptoms even more miserable is the dust mite.

Dust mites are microscopic organisms living in the inviting dampness of a basement. These tiny creatures invade your living space and feed off of pet dander and human skin cell flakes. They thrive in moist places like basements. The dust mite problem is so pervasive that according to the American Academy of Allergy Asthma & Immunology dust mite droppings is the most common trigger of perennial asthma symptoms.

Allergy Solution: Eliminate Moisture

When you combine mold spores, dust mites and allergies you have a prescription for feeling miserable. The excess humidity in your basement allows dust mites to breed and mold to colonize on wet basement walls, floors, carpeting and furniture. These irritants then drift up into your home via natural airflow patterns to compound your allergy symptoms. Ignoring the problem will steadily make your allergy symptoms worse as mold and dust mites continue to multiply. By eliminating their breeding ground you rid your basement of these invasive nuisances.

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