Do Automatic Foundation Vents Really Work?

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Sounds like a great idea doesn’t it? Install automatic foundation vents and you’ll never have to remember to open and close them as the seasons dictate. But do they really work, and more importantly, do your vents need to open and close?

Causes Excess Moisture

One of the big selling points for installing automatic vents is they help control moisture underneath your home. Excess condensation and dampness can lead to wood rot, mold and mildew. Eventually it can lead to foundation piling movement and is an attraction for rodents, insects and termites. Foundation vents were included as a method of both keeping out moisture such as rain, snow and ice, while at the same time during the warmer months, allowing air to circulate and keep the space dry. 

Creates Humidity 

Unfortunately no one was paying much attention to a little thing called relative humidity. When the warmer outdoor air is in contact with the cooler crawl space air, condensation occurs. Then for every degree the warmer air gets cooler, the relative humidity increases by a little over two percent. So while it might be pretty comfortable outside, underneath your home, inside that enclosed foundation, the humidity could easily double. 

This humidity is frequently the major culprit of the above mentioned crawl space moisture concerns. Everything from the floor joists to exposed insulation can become saturated and turn into a mold and mildew Petri dish. If this excess moisture is never able to thoroughly dry out a homeowner could easily be facing thousands of dollars in repairs to the floor joists, foundation pilings and even the wood subflooring underneath your home’s first floor. 

Open Is Best

Ideally foundation vents should be closed year round since condensation and high humidity can be just as much of a problem in winter as in summer and spring. Though many homeowners are hesitate to leave the vents shut during the summer, believing higher ambient temperatures will help to decrease any extra moisture. When in reality all those open vents are doing is making the crawlspace damper, causing the interior of your home to become more humid and your HVAC system to work harder. 

Having crawlspace moisture problems at your home? A professionally installed vapor barrier or encapsulation system can help. Call Scout’s Pest Control today at 864-469-4999 and schedule a no-obligation consultation.