Opening and closing crawlspace vents

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Opening and closing crawlspace vents

Source: Lynch Building Inspection Services Ltd. of Nelson, BC.
Originally appeared in The Nelson Express.

My home has a crawlspace under it. I know I’m supposed to be opening and closing the vents but I don’t know when.

Here are a few tips that will help keep your crawlspace healthy. Open the vents in early spring and don’t re-seal them until late fall. Make sure the screens are in good repair and seal all other openings to ensure insects and small animals don’t take up residence under your home.

If your crawlspace is not heated consider insulating the underside of your floor. Hold the insulation in place with chicken wire or 1″ x 4″ strapping. Install several vents to ensure there is good air circulation, especially at shallow “hard to get to” areas. If you don’t have an access hatch or service trenches to the shallow areas of the crawlspace it would be beneficial to do so for periodic inspection of your home’s structure. If you have a dirt floor install a 6-mil U. V. rated polyethylene vapour barrier throughout. Overlap and seal the plastic seams with “tuck tape” and caulk the plastic tight to pony walls, footings, plumbing pipes and foundation walls with acoustic sealant or tape. When complete, you will have created a much healthier crawlspace for you and your home.