The Passive Foundation Vent can be used to provide foundations with passive ventilation or can be used along with a fan-powered crawl space ventilator for maximum effectiveness. This unit not only provide ventilation during the warmer months, but also includes a winter guard, which allows homeowners to fully seal the crawl space during the heating season--greatly improving the home's energy efficiency. This vent can be completely installed from the outside of the crawl space in minutes.

Features:

• Increase crawl space air flow to decrease moisture
• Reduce heat loss through crawl space vents during the heating season
• Help prevent pipes from freezing
• Has a heavy duty screen and high quality ABS