I was at a house yesterday where I asked the seller why he was using a long flex hose running across the floor from his dryer to a vent on the side of his house and not just run a smooth wall steel duct up through the ceiling, across the attic and out the side of his gable roof wall. He said at one time he did, but when the city building inspector came to inspect his new water heater, the inspector pointed to the vertical duct and told him that was a code violation.
I called an inspector friend of mine and he said the flowing lint will loose energy and fall back down, creating a fire hazard. Made sense to me at the time.
I furthered researched IRC chapter 15, section M1502 and I see nothing against vertical rises.
So is running the dryer duct up to the attic and out the side of the house a code violation?
The maximum developed length of a clothes dryer exhaust duct shall not exceed 35 feet from the dryer location to the wall or roof termination. The maximum length of the duct shall be reduced 2.5 feet for each 45-degree (0.8 rad) bend, and 5 feet for each 90-degree (1.6 rad) bend. The maximum length of the exhaust duct does not include the transition duct.
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ddivito
(Dennis DiVito, VA License # 3380 000170 NRS)
5
Dennis,
Normally I would agree, but he removed the vertical pipe and I don’t know what kind of pipe it was. He has 4" pvc in the attic which was not removed. So if the inspector was pointing to the pvc, than yes I see the problem.
So, speaking hypothetically, would smooth wall steel up and out be acceptable?
I agree but I’ve never seen a dryer vent “‘installed” in a basement. All I’ve every seen were homeowner installed.
And I’m impressed how quickly you thought of that, it told me a couple days to think of that.
I see them vertical through the wall and attic all the time. What I see now is this sticker on the vent wall box detailing the vent equivalent distance. I let the client know that it is very important their dryer is rated for that distance.