Should you winterize your homes crawlspace for the winter?

foundation vent covers on homeAs the weather starts turning colder, many homeowners will start to look at the exterior of their home to find ways to save on energy usage by weatherizing faucets, windows and crawlspace vents.  Protecting exterior faucets and sealing gaps in windows and doors is a great way to protect your homes plumbing and save on heating costs, but many homeowners have questions on sealing the exterior vents on their homes foundation.

First before making the decision to seal up those vents, it can be helpful to understand why they’re there in the first place.

Foundation vents, what’s their purpose?

Just as their name suggests, foundation vents provide critical venting to your homes crawlspace.  This venting is important as it ensures moisture is not trapped in a homes crawlspace where it can wreak havoc on the underside of the home.  Excessive moisture in a crawlspace needs to be avoided because it can create the following problems:

  • Can introduce moisture to the structural wood under your home, which can cause rot.
  • Creates a moisture rich environment that some wood destroying pests thrive in, such as: Moisture Ants, and Dampwood Termites.
  • Can saturate the insulation under the homes flooring, which then loses its insulating properties rendering it useless.  In addition, if the insulation backing becomes wet, it will need to be replaced.
  • Moisture can create an environment that mold will thrive in. Molds like the dreaded black mold are an expensive problem for any homeowner to fix.
  • Moisture in a crawlspace can create a musty smell that can travel through your homes HVAC ducting into the homes living space.

Your homes crawlspace, when set up correctly with unobstructed vents, and a vapor barrier that’s in good condition provides an air barrier between your homes structure and the ground.  This air barrier and the venting provides air flow that should consistently keep the ambient moisture in the crawlspace relative to the ambient moisture outside the home.

Should foundation vent covers be used during the winter months?

Understanding the function of your homes foundation vents for the health of your homes crawlspace, many people question if foundation vent covers should be used at all.  Foundation vent covers can be helpful in extreme cold situations, where a home’s underside plumbing is at risk, in these situations, foundation vent plugs can keep fast moving cold air out.  In situations where cold weather is of concern, foundation vent covers can be used, but it’s advisable to only use them a few weeks at a time, removing them to move the old air out for a few days or a week, before replacing them.

Home crawlspace inspections

Every homes crawlspace situation is different.  The above is only provided as a guide to your homes crawlspace, for homeowners that have concerns regarding the overall health of their homes crawlspace area, hiring a reputable crawlspace contractor to do an inspection, can save sometimes thousands of dollars in damage in the future.

Foundation Vent Covers – Should you use them on your home? in Portland OR and Vancouver WA

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