Building codes generally require working vents in the crawlspace to allow outside air to circulate under the floor in the summer to prevent moisture buildup that, among mildew and mold, encourages wood rot.
Which is better vented or unvented crawl space?
Unvented. The principal perceived advantage of a vented crawl space over an unvented one is that venting may limit radon and moisture-related decay hazards by diluting the crawl space air. Additionally, providing a vented crawl space may make sense in flood-prone areas such as coastal zones subject to hurricanes.
What is the best way to ventilate a crawl space?
Airing out your Crawl Space
- Transfer a small supply of heated air from the HVAC system into the crawl space.
- Use an exhaust fan to move air from the crawl space to the outside.
- Install an air intake or dehumidifier system.
