Roof and surface water must be controlled to maintain a dry basement or crawl space and prevent mold growth and indoor air quality problems. This means keeping gutters cleaned out and aligned, adding downspout extensions, installing splash blocks, and building up the grade so that roof and surface water are diverted away from the building. 

Additional Steps:

  • Install an overlapped 6 mil plastic vapor barrier over all crawl space dirt.
  • Insulate plumbing pipes and ductwork.
  • Seal all cracks or holes in the foundation or basement walls.
  • Maintain indoor and crawl space humidity levels close to 50% year-round.
  • Check that all kitchen, bathroom and clothes dryer exhausts vent to the exterior and ducts are without holes or tears.
  • Periodically check attics, crawl spaces and basements for plumbing leaks or signs of moisture intrusion.
  • If a sump pump is present, the crock or well should be covered and the pipe should discharge water at least 2 or 3 feet from the building.
  • Trim back foliage one foot away from the building.
  • Close foundation vents in summer.

Other Sources of Interior Moisture:

  • Condensation caused by indoor humidity that is too high or surfaces that are too cold. (Reduce humidity or add insulation.)
  • Humidifiers
  • Gas ranges/ovens
  • Unvented combustion heaters
  • Faulty vented gas appliances
  • Firewood stored indoors
  • Cooking and dishwasher drying cycle
  • Houseplants and aquariums
  • Bathing and showering
  • Hanging clothes to dry indoors
  • Refrigerator defrost cycles and drip pans

Finally, you may want to consider the Humidex Moisture Control and Ventilation System. Humidex is your solution for excess humidity and poor indoor air quality. This innovative ventilation unit provides a healthier home environment by improving the air quality and expelling moist air that nurtures molds and creates condensation. Visit the Humidex page for more information.