Exhaust vent outdoor opening size?
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Okay, this is a nitpicking detail, but what does this part of the IRC mean?
R303.6 “Air exhaust and intake openings that terminate outdoors shall be protected with corrosion resistant screens, louvers, or grilles having an opening size of not less than 1/4″ and a maximum opening size of 1/2″, in any dimension.”
Does this mean that the holes in an exhaust vent have to be smaller than an 1/2″ circle? That doesn’t line up with most of the vents that I’ve seen on the market, especially dryer vents.
–John
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Replies
John,
The provision is in the "Ventilation" section of the code. It pertains only to intake and exhaust openings for ventilation systems. If you have a clothes dryer exhaust vent, it doesn't have to comply with this code provision.
It refers to the need for screening or hardware cloth to exclude large insects, rodents, and birds.
-- Martin Holladay