Basement Dehumidifier Facts:  Solve Basement Moisture Problems


The basement of your home is either completely or partially below ground level. It's typically used as a utility  space that houses furnaces, water heaters, breaker panels or fuse boxes, car parks and air conditioning systems. It can also accommodate the electrical distribution system and the cable television distribution point.

The location of basements leaves them susceptible to moisture problems. The three main sources of basement moisture are:

  • Rainwater and Groundwater
    When 1 inch of rain falls, about 1,250 gallons of water falls on the roof of an average-sized home. Without proper grading, gutters and downspouts, some of this water flows into the basement.
  • Interior Moisture
    People and their activities can generate moisture inside of basements. Humidifiers, unvented clothes dryers, showering and cooking can all raise humidity levels. There may also be moisture contained in new concrete after construction.
  • Ventilation with Humid Outside Air
    During hot summer weather, many provide fresh air by opening basement windows. Hot and humid outside air condenses on the cool basement wall and floor surfaces.

Why prevent excess humidity?

Excess humidity in the air causes basements to smell musty and feel unhealthy and damp. This dampness may damage furniture, furnishings and stored items as well. Eventually, excess humidity encourages rust, mildew, mold and odors to develop and anything stored in the basement is vulnerable. If anything of value is stored in your basement, or if it's used as a living space, it's important to keep the moisture levels low by using a basement dehumidifier.

What is ideal basement humidity?

The EPA recommends 50% relative humidity to protect your family and the investment you've made in your home. Relative humidity levels rising above 70% stimulate the growth of mold, mildew, bacteria and other biological allergens, which generate musty basement odors. Smaller environments inside the basement, such as underneath carpeting, rugs or inside storage boxes also need humidity control.

Adult dust mites only have a 4 to 11 day lifespan in relative humidity below 50 percent. Humidity must be kept at or below 50% because dust mites in the protonymph stage are in a dormant larval state and can survive for several months waiting for high humidity conditions to return.

basement-moldCan I use my air conditioner as a basement dehumidifier?

Some people believe that air conditioners alone can satisfy all of your home humidity requirements, but it's simply not true. They remove humidity as a byproduct of cooling but are ultimately designed to control temperature, not humidity. Especially during the spring and fall seasons, when the temperature outside is cool and the air conditioning is off, your home may become uncomfortable.

By using a basement dehumidifier, you remove the moisture load from the air conditioner, allowing it to cool more efficiently. Your home will remain more comfortable and require less cooling, which saves money and energy.

Will a portable dehumidifier or air filter work in my basement?

Common portable dehumidifiers aren't the answer. Most can't perform well in cool basement environments. Also, more than one unit may be needed to properly dehumidify the entire area. Some other disadvantages include messiness, noisiness and freezing up over time.

Air filters won't eliminate dust mites and mold. They can only capture airborne particles. Since the dust mite allergen is large and dense, it doesn't remain airborne long enough for air filters to capture it. People are exposed to allergens in their home when they come into direct contact with their breeding ground. Air filtration devices don't prevent this from occurring.

Basement Dehumidifiers to the Rescue!

Basement dehumidifiers are the best solution for removing damp mildew or odor associated with basements and to prevent mold from growing. Basements tend to be cool environments, so basement dehumidifiers with low temperature operation functions are ideal. They continue to draw moisture out of the air even when temperatures are low.

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