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Community and Q&A

Soffit roof venting

Matt McIver | Posted in General Questions on

I was wondering if there is a formula (Code or otherwise) to determine the width of a continuous soffit needed to vent  a rigid GAF Cobra ridge vent. The number should allow enough air so that it is pushing up toward the ridge. Also, how would I address insects that may get into vents with larger openings without decreasing the air flow.

Thanks a bunch!

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  1. Expert Member
    Malcolm Taylor | | #1


    Each vent product should include a specification that shows the clear vented area it provides. So for instance, a perforated aluminium soffit would show how many sq inches of ventilated area it gives per sq foot.

    You avoid insects gaining entry by using a material with small enough holes that they can't get through. That is accounted for in the clear vented area of the material.

    The amount you are aiming for is governed by code. Here is a link to common requirements:

    1. Matt McIver | | #2

      Thanks Malcom, I will check those when I get started on that project.

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