Below Grade Chimney and Tee

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BG2022

New Member
Sep 6, 2022
8
Maryland
Hello,

I'm in the process of getting a wood burning stove installed in my basement. The installation is almost complete but part of the chimney and tee are below grade (see pic) which I was not expecting. Everything was supposed to be above grade when I signed the quote. The tee/chimney cannot be buried I'm told, and I'm extremely worried about my basement flooding, and the longevity of the chimney being below grade. There is currently a primitive cover made out of sheet metal on top of this (and tarp on top of that), but it's not a long term solution. This install is obviously not ideal, but are there any ways to salvage this job and not need to worry about leaks every time it rains? I'm on the verge of just taking everything back out, and restoring to the original but I'd be out of a hefty deposit.. Advice would truly be appreciated.

chimney.jpg
 
At times there is little choice but to do this. The main concern will be leaves blowing into the well. This can be prevented with a screen system. The one thing that doesn't look right is the use of elbows to make the offset. Last I checked, DuraTech offset elbows were only permissible indoors with the elbow straps attached to the joists or roof rafters. I'm not sure if DuraVent has changed that ruling or not.
 
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At times there is little choice but to do this. The main concern will be leaves blowing into the well. This can be prevented with a screen system. The one thing that doesn't look right is the use of elbows to make the offset. Last I checked, DuraTech offset elbows were only permissible indoors with the elbow straps attached to the joists or roof rafters. I'm not sure if DuraVent has changed that ruling or not.
Thanks for the reply! There will definitely be some type of cover to keep leaves and debris out. I'm hoping to put some type of pavers over that cover that I can somewhat easily remove for maintenance if needed. I'm more worried about water getting in there and finding its way into the basement, or prematurely corroding the tee/chimney etc. I'm just really worried that this is not a normal install that will have issues down the line, and that I'm creating more problems for myself than solutions. The installer said he's never installed pipe like this below grade, but the salesman told me they do this all the time.. I'll definitely look into the elbows. Thanks again.
 
Has it been leaking? Are there gutters or diverters In that corner?
 
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It looks like there are hangers on the rim joists. Will this get a porch surrounding it?

Has it been leaking? Are there gutters or diverters In that corner?
I get the most runoff over the gutter guard in the two inside corners like this. Debris constantly builds up in the valleys and collects at the bottom in the inside corner of the gutter. Nothing I have done has cured this. I have to clean the valleys of needle and leaf buildup at least 4 times a year.
 
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Has it been leaking? Are there gutters or diverters In that corner?
It has not been leaking, but it's only rained once since the install started last Friday.. and it has a temporary sheet metal cover on that, and a plastic tarp on top of that. Looking "north" on the pic there are gutters. The roof on the east/right of the pic slopes south, so away from the well/chimney.
 
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It looks like there are hangers on the rim joists. Will this get a porch surrounding it?


I get the most runoff over the gutter guard in the two inside corners like this. Debris constantly builds up in the valleys and collects at the bottom in the inside corner of the gutter. Nothing I have done has cured this. I have to clean the valleys of needle and leaf buildup at least 4 times a year.
There was a small porch that was mostly removed for installation. I was planning on taking it down anyways eventually and laying down some pavers. Below the joists/porch is a concrete slab which kept water away from the house nicely. They dug that corner up for the chimney install. Perhaps rebuilding the porch with a cutout for the chimney with 2" clearance and a storm collar around the opening with well placed screws that can be removed for easy access when needed in addition to the sheet metal cover will do the trick. Iv'e had bad experiences with water infiltration in the past so I feel like an idiot for opening myself up to another potential issue.
 
There was a small porch that was mostly removed for installation. I was planning on taking it down anyways eventually and laying down some pavers. Below the joists/porch is a concrete slab which kept water away from the house nicely. They dug that corner up for the chimney install. Perhaps rebuilding the porch with a cutout for the chimney with 2" clearance and a storm collar around the opening with well placed screws that can be removed for easy access when needed in addition to the sheet metal cover will do the trick. Iv'e had bad experiences with water infiltration in the past so I feel like an idiot for opening myself up to another potential issue.
Your options are make a cover or add a drain to that well
 
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