GIMME SHELTER- Damp damage: Control that moisture

Corin Major, Airflow Diagnostics Institute 

Q: I'm worried about moisture damage to my home. My basement is damp, and I've noticed some of my walls have been sweating. What can I do?

A: Given that water and moisture are among the leading causes of property damage, it's worth nipping a moisture problem in the bud. Not long ago, we discovered a very small leak in a homeowner's bath/shower drain that had gone undetected for years. The moisture had saturated the floor joists, and mold had deteriorated the wood so badly that the bath/shower was about ready to drop through the floor. Needless to say, even a small bit of moisture intrusion can have a disastrous effect over time.

If you have a moisture problem, whether in your walls, floor, crawl spaces, or basement, the first step is finding the source. Leaky faucets or drains can be heard and will sometimes form water stains on ceilings and walls. If you suspect a leak, have a plumber check for it immediately. 

     Moisture problems behind walls and in crawl spaces can also be caused by leaky ducts in your cooling system. When cool air blows through the leaks, it creates pockets of condensation in the same way a bottle of water from your fridge sweats when you leave it out on a humid day. In this case, you'll need to make sure the ductwork for your cooling system is airtight.  

      If you have a damp basement, it's almost always caused by water intrusion from the outside; from poor grading on your property or improper downspouts on your roof that don't direct water away from the house. If you have an older house, there may also be an improper moisture barrier around the base of your concrete foundation. You may need to install drain pipe around the perimeter to facilitate the flow of water away from the house.

     I also recommend professional mold testing to determine if you have toxic or allergen molds. Once it's detected, a professional can remove airborne and surface molds.

     Since Charlottesville experiences up to 80 percent average humidity in the warmer months, getting a high-efficiency dehumidifier might be a good idea as well. If you do decide to get one, consider a commercial-size unit, as the ones available at home and garden stores simply don't have the capacity to remove an adequate amount of moisture. 

Corin Major