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Chimney top, cap over multiple flues

DRP

Gold Member
Joined
Sep 14, 2010
Messages
529
Location
VA
We have a chimney with 3 tile flues that serve 1, an outside fireplace, 2, an indoor woodstove, and 3, a spare running to the basement for futre possible use, fuel I'm not going to guess. May we put them all under one common raincap? I'm not finding a cite one way or the other.
 
DRP said:
We have a chimney with 3 tile flues that serve 1, an outside fireplace, 2, an indoor woodstove, and 3, a spare running to the basement for futre possible use, fuel I'm not going to guess. May we put them all under one common raincap? I'm not finding a cite one way or the other.
I did it! One poster suggested it would not work because one flue might draft from another, course only one of mine was a wood stove. I installed a CO detector in the mechanical room an three months later, No Problems.View attachment 1324View attachment 1325BillView attachment 567

View attachment 568

View attachment 567

View attachment 568

/monthly_2012_03/ShopAddn295.jpg.0648313f73a3974cd8ce7ce641583bdb.jpg

/monthly_2012_03/ShopAddn296.jpg.cac48ca9aec674340f8ff8825aa9b177.jpg
 
Thanks Guys, I had heard the same thing Bill but couldn't find anything prohibiting it. The situation I'm talking about is a bit different than Bill's, we want to put all the flues under one common raincap.

The flues are side by side and we would like to weld a shallow hip roofed screened top.

IMG]http://i180.photobucket.com/albums/x109/windyhilll/chimney005opt.jpg[/img]

I've also been wondering how much clear air to put between the top of the flues and the cap.
 
DRP said:
Thanks Guys, I had heard the same thing Bill but couldn't find anything prohibiting it. The situation I'm talking about is a bit different than Bill's, we want to put all the flues under one common raincap.The flues are side by side and we would like to weld a shallow hip roofed screened top.

IMG]http://i180.photobucket.com/albums/x109/windyhilll/chimney005opt.jpg[/img]

I've also been wondering how much clear air to put between the top of the flues and the cap.
Creating a cap for all three will work. The biggest concern is to leave enough space in the height to allow all three to draft freely. The draft from the fireplace can move upwards of 300 cfm with a roaring flame.
 
DRP said:
Thanks Guys, I had heard the same thing Bill but couldn't find anything prohibiting it. The situation I'm talking about is a bit different than Bill's, we want to put all the flues under one common raincap.The flues are side by side and we would like to weld a shallow hip roofed screened top.

IMG]http://i180.photobucket.com/albums/x109/windyhilll/chimney005opt.jpg[/img]

I've also been wondering how much clear air to put between the top of the flues and the cap.
Hi DRP,

If you're referring to the actual chimney cap, the part that fastens to the listed flue, that part is part of the tested assembly. I don't believe that you can fabricate your own and still claim the protection of the UL listing. That "Chimney Cap" is designed to minimize draft disturbances caused by the wind.

If you're referring to the rain cap that surrounds the flues and flashes the top of the chimney enclosure as I did, I believe you're good to go.

Bill
 
Bill, it's a solid masonry chimney, 3 terra cotta flue liners. Here's a rough sketch, there will be expanded metal mesh to keep critters out.

chimneyraincap.jpg


Looks like I muffed the photo, trying again;

chimney005opt.jpg
 
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