How to Solve Damp and Humid Basement Problems

The humid summer months are more than uncomfortable. Humidity is also a liability. Basement moisture problems can pose significant health, structural, and financial troubles.

Does your basement smell damp and musty? Are there any wet spots or water trickling down the walls? What about standing water? If you have a damp and humid basement, you’ll know.

Humid and Damp Basement Problems

Damp basements have become so common as to turn into a cliché. Unfortunately, this can cause some serious issues:

  • Mold and Mildew
  • Rot
  • Structural Damage
  • Pest Problems
  • Indoor Air Quality (IAQ) Problems
  • Peeling Paint and Wallpaper
  • Buckling Floor Materials
  • Property Destruction

If you have a damp or humid basement, reducing your basement moisture should be a prime concern. A minor home improvement could easily turn into a financial disaster. Fortunately, basement water problems are solvable.

How to Solve the Problem

There are three main reasons for a damp or humid basement:

  1. water leak(s)
  2. water Infiltration (rain or groundwater)
  3. high humidity

If you have a leak somewhere in your system, it should be easy to tell. Turn off all of the water and water-using appliances in the home. Then, locate your main water meter (usually located near the front curb) and open it up. Most water meters have a leak detection dial. If the leak detection dial is spinning, you have a leak somewhere. If the leak detection dial is still, you don’t have any leaks. If there is a leak in the basement, contact a professional plumber.

Often, water from the outside enters the home because the grading or slope is not properly diverting the water.

Other causes of water infiltration include:

  • Improper or damaged gutter and downspout systems
  • Failure to slope ground water away
  • Missing or nonfunctioning subsurface drainage system

If you think water is coming in from the outside, spend some time evaluating the gutters, downspouts, and surface grading. Consider installing downspout extenders to help direct water away from the home.

High humidity is another problem. Interior humidity levels can rise due to water leaks, unvented clothes dryers, humidifiers, cooking, bathrooms, exterior humid air, and more.

You also want to make sure there is no water pooling near your indoor air handler. If your air conditioner’s condensate drain system isn’t working properly, contact a professional HVAC technician to fix the problem.

Step-by-Step Humid Basement Solution

  1. Find and control the moisture source
  2. During summertime, don’t ventilate outdoor air
  3. Improve grading, gutter, and downspout system
  4. Install or improve exterior drainage system
  5. Consider installing a sump pump
  6. Speak with a professional HVAC company about ventilation and humidification improvements


When it comes to basement moisture problems, address the source first. After removing and controlling the source, you can maintain proper indoor humidity levels with dehumidification and ventilation.

While dehumidification can reduce the symptoms of a damp and musty basement, it shouldn’t be seen as a permanent solution. In fact, if you ignore the source of your moisture problems and try to dehumidify the problem away, things could get worse.

For help lowering the humidity and improving the ventilation of your home, contact the professionals at Service Champions. Learn more about improving indoor humidity.

We can inspect our home for moisture and humidity problems and recommend solutions for your specific situation.

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