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Clarify the ASHRAE 62.2 ventilation rate spec.

wolley | Posted in General Questions on

It says 1cfm per 100 square feet of occupiable space and 7.5cfm per occupant
My question: for how many minutes? … 1cfm for an hour, 6 hours, all day?

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  1. GBA Editor
    Martin Holladay | | #1

    That's the spec for continuous ventilation (24 hours per day). If the calculation tells you that you need 100 cfm, you can ventilate continuously at 100 cfm, or (for example) for 30 minutes every hour at 200 cfm.

    Of course, many homeowners choose to operate their ventilation equipment at a rate that doesn't meet ASHRAE 62.2.

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