“Barometric damper” air inlet for room with woodstove
Wondering if someone can identify a specific product for this application. The merits of the application might entice some to debate, but I am neither a code writer nor building inspector, just a guy caught between them.
I have a job with a woodstove in an art studio space. It does not have a direct connection from the firebox to an outside air duct, and it would be difficult and costly to accomplish that, because the stove is on a concrete slab, it is against a wall with a garage on the other side, and it’s 12′ from any exterior wall.
The code states that if the stove is installed in existing construction on a slab, that combustion air can be supplied to the ROOM via a “barometric damper”. What I would like to do (and about the only thing I can do) is install some type of through-the-wall inlet with the aforementioned barometric damper within it. The American Aldes airlets do not qualify, per the language on their instruction sheets. There are barometric dampers intended for use with HVAC systems, typically involving a short section of round duct with a damper inside and a weighted arm outside, which can be adjusted for pressure. The problem with the arm outside is that it won’t easily fit in the wall, and putting on the inside of the room will be objectionable.
Anyone know of any sort of damper or valve that would work for this purpose? Ideal candidate would be 4″ or 5″ diameter.
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Replies
David,
Do you have a code reference or code citation? I have never heard of a barometric damper being used for this purpose.
Martin, here it is. This is from the Washington state legislative website, adopting what I believe is part of the IMC... http://app.leg.wa.gov/wac/default.aspx?cite=51-51-1006
Exception 2 is what would apply in this case.
What I recall hearing of, and am hoping to find, is something that incorporates some sort of fabric "bladder" inside a short piece of duct. I've talked to a fairly large number of people so far without any hits.
David,
Here is a link to the type of damper you are talking about (it's called the Cape Damper, and it's made by Tamarack Technologies):
Tamarack Cape Backdraft Damper
Although I'm confident that this is the product you are talking about, I'm not sure whether it's the type of damper that the code writers had in mind for the purpose you intend.
By the way, Tamarach Technologies is a good company that makes quality products -- but they get a demerit for their cheesy choice of a photo to illustrate their web page that sells backdraft dampers.
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Martin, you guys could use images like that on GBA and receive a lot more web traffic...
I think I'll run the Tamarack product by the building inspector and see what he thinks.
David,
I looked at the photo of the sofa for the longest time -- but I still can't find the backdraft damper. Maybe it's under one of those big white cushions.