A damp crawl space calls for Moisture Control
Moisture control in your crawl space area is paramount to the successful eradication of subterranean termites in your structure. When moisture builds up in your crawl space your chances of termite and wood borer beetles infestation goes up with it. Reducing the amount of evaporation moisture reduces the chances of termite infestation. Many termite infestations begin when a leaky pipe or other moisture conditions become serious. In another section of this TermiteMD, I cover doing a crawl space inspection. Check it out if you’ve never searched for termites in a crawl space before.
If you don’t have a moisture meter, look for mildew or mold. Wood will generally have about 17% moisture content in it when mildew begins to grow. This would be a sign I would look for to judge whether this structure could use a moisture barrier or vapor barrier. If you need to install one here how to do it.
Installing a Moisture Control Vapor Barrier
- The treatment goal is to cover 70% to 80% of the dirt in the crawl space. This will reduce the amount of moisture getting into the wood under your house from groundwater evaporation. Leave about 3 ft uncovered around the perimeter and leave an area in the middle around the piers uncovered.
- Purchase a roll of poly 10 x 100 x 4 mils thick. This is the easiest size to handle under a home.
- Roll the poly out and use a knife to cut it to size.
- Unfold this piece and move to the other side of the crawl space.
Add proper ventilation Temp Vents
- Your crawl space should have at least one vent on each side to allow cross ventilation. Some parts of the county may require even more ventilation. You can never have too much crawl space ventilation.
- You may want to buy temperature control vents. They will close by themselves when the temperature goes down to around 40 degrees. When you vents are closed they will not allow any more cold air under your structure. This will save on your heating bill by allowing the air underneath your home to warm. When the temp goes back above 40 degrees the vents open allowing needed air circulation. Temp vents are not expensive and are easy to install. Loews carries them for around $15 each. Each vent is self-controlled, no batteries or electric hook-up. A spring type bi-metal thermostat moves when the temp changes; thus open and closed the vent on its own. Some exterminators sell and install these vents as part of their moisture control programs.