Sizing Unvented Crawl Space Opening

[Francis Vineyard]

Any other suggestions on how size the openings?

R408.3 Unvented crawl space.

2.2.

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Conditioned air supply sized to deliver at a rateequal to 1 cubic foot per minute (0.47 L/s) foreach 50 square feet (4.7 m2) of under-floor area,including a return air pathway to the commonarea (such as a duct or transfer grille), and perimeterwalls insulated in accordance with Section

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N1102.2.9;





Francis

 

[Gregg Harris]

Any other suggestions on how size the openings?

R408.3 Unvented crawl space.

2.2.

​

Conditioned air supply sized to deliver at a rateequal to 1 cubic foot per minute (0.47 L/s) foreach 50 square feet (4.7 m2) of under-floor area,including a return air pathway to the commonarea (such as a duct or transfer grille), and perimeterwalls insulated in accordance with Section

​

N1102.2.9;





Francis

Is 2.2 your choice for the circulation?

 

[Francis Vineyard]

Gregg, for new construction it is the preferred method. A continuous running fan is undesirable and noisy.

Francis