Smart crawl space vents good for you and your home.

Non-powered vent above


Automatic (non powered)crawl space vents are very easy to install in new construction and require virtually no maintenance.

Foundation or Crawl space Vents
Non-powered, Automatic Foundation Vent will open and close automatically using a heat/cold sensitive coil. The louvers open completely at approximately 72°F and completely close at approximately 38°F.

This is a good idea because it prevents spaces from becoming to humid and hot as well as cold and potentially freezing temperatures under conditioned space. When we can control the temperature and moisture adjacent towards the heating or cooling envelop we can maximize our heating and cooling efficiency.


To Specify:
Whenever possible, vents should be placed on all sides of the foundation. This will create an intake/exhaust system that delivers a steady flow of air. One vent should be installed for each 8 to 10 feet of foundation wall.

Most building codes require 1 square foot of open ventilation area for every 150 square feet of crawl space. Temp Vent Automatic Foundation Vents have 50 inches of net free area per vent. Therefore, you should install one vent for every 50 square feet of crawl space.


For crawl spaces with polyethylene installed, on 80-90% of the floor, the ventilation requirement changes to 1 square foot of ventilation for every 500 square feet of crawl space with a minimum of 4 vents installed to provide cross ventilation. For crawl spaces with polyethylene, install at least one vent for every 500 square feet of crawl space.


Remember to Tread Lightly or Less
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Eric H. Gjerde AIA
Architect