Where to put the "T" for installation through the wall - does it have to be mounted to the wall?

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Chestnutty

New Member
Mar 3, 2024
19
Chestnutty
Hi there! I am new ;-)
We are building a log home and would like to vent the flue pipe through the gable wall in the great room. The penetration is through the wall and pretty far up to miss the roof that is over the porch. Of course now we also have to miss the soffit.
My question is: Do you need to install the "T" for an outside connection directly mounted to the wall or can you go out with a length of pipe first and then do the 90 degrees for the vertical pipe? I don't have the option of going from a "T" to a 30 degree offset since this is not enough space between where the pipe comes through the wall and where the soffit starts.
I cannot find any information on this and all the diagrams and installs I have seen have the "T" section mounted directly to the wall and then include off-sets for the soffit.

The whole outside assembly will be within a chase so there are lots of options for support brackets. I just don't know whether this will pass code.
We will be installing this with the help of our builder - the quotes I have received so far for an install of this kind (minus chase) are in the range of $15-16K!!! I can't afford that :)

Help and insight greatly appreciated. I attached a drawing of what I am talking about - hope it makes sense! I am not an artist ;-)

Thanks much!!

View attachment Chimney installation.jpeg
 
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Hi there! I am new ;-)
We are building a log home and would like to vent the flue pipe through the gable wall in the great room. The penetration is through the wall and pretty far up to miss the roof that is over the porch. Of course now we also have to miss the soffit.
My question is: Do you need to install the "T" for an outside connection directly mounted to the wall or can you go out with a length of pipe first and then do the 90 degrees for the vertical pipe? I don't have the option of going from a "T" to a 30 degree offset since this is not enough space between where the pipe comes through the wall and where the soffit starts.
I cannot find any information on this and all the diagrams and installs I have seen have the "T" section mounted directly to the wall and then include off-sets for the soffit.

The whole outside assembly will be within a chase so there are lots of options for support brackets. I just don't know whether this will pass code.
We will be installing this with the help of our builder - the quotes I have received so far for an install of this kind (minus chase) are in the range of $15-16K!!! I can't afford that :)

Help and insight greatly appreciated. I attached a drawing of what I am talking about - hope it makes sense! I am not an artist ;-)

Thanks much!!

View attachment 325414
Just go straight up through the roof it's cheaper, easier, works better, and is way easier to maintain
 
I was trytng to avoid that since I did not want to compromize the integrity of the roof. None of my plumming stacks go through the roof either - they vent through the gable.
 
I was trytng to avoid that since I did not want to compromize the integrity of the roof. None of my plumming stacks go through the roof either - they vent through the gable.
I get that. But in the process you are going to make a chimney that easily costs twice as much doesn't work as well and is a real pain to maintain
 
We are not planning on installing a chimney but running the pipe externally as is done in many houses, just enclose it in a chase... our builder feels this is easy to do.. amd I missing something here?
 
We are not planning on installing a chimney but running the pipe externally as is done in many houses, just enclose it in a chase... our builder feels this is easy to do.. amd I missing something here?
That pipe is a chimney. And yes what you are proposing is certainly doable. But again it will cost much more. It won't draft nearly as well as straight up. And it will be a real pain to clean setup that way. Going through the roof really isn't a big deal at all. I do it many times a year with no issues at all
 
Thank you! I really appreciate your insight here, esp. that it won't draw well! That is certainly something to take into consideration, esp. since this is our primary source of heat and the house is pretty "tight"...
 
Properly flashed, roof penetrations will never leak. Especially near the peak of steep roofs. Compromising the integrity and performance of a chimney to avoid penetrating a roof is ridiculous.

But to each his own.
 
Thank you for that feedback and for putting me in my place with this "ridiculousness".... I am just a mere homeoner asking for advice...
 
Thank you for that feedback and for putting me in my place with this "ridiculousness".... I am just a mere homeoner asking for advice...
Oh we know that and don't mean to make you feel bad about asking questions at all. But you asked for advice and got it. As a pro I would refuse to do an install the way you want it.
 
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Thanks again! That is EXACTLY what I was hoping to hear and why I joined - am I trading one problem for another - The local installers that I talked to would have done the install.. noone mentioned what I am getting myself into...
 
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Based on what is being described, a straight-up, through the roof install should be under $4,000. Stove pipe is much less expensive than chimney pipe and there will be no chase construction expense. Just be sure the installer is fully competent. If there is a metal roof, then it should have a proper metal roof flashing, not a flexible silicone rubber one.
 
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Thank you! It is a metal roof on a log home. The roof insulation is extensive - 3/4 inch tongue in groove boards (since cathedral ceiling inside), roof paper, then 2 x 3 inches of high density foam insulation, then OSB and then roof paper again. Its massive! Will make sure it has a metal flashing.
 
Thank you! It is a metal roof on a log home. The roof insulation is extensive - 3/4 inch tongue in groove boards (since cathedral ceiling inside), roof paper, then 2 x 3 inches of high density foam insulation, then OSB and then roof paper again. Its massive! Will make sure it has a metal flashing.
That honestly is a very easy roof to install a chimney through. Is it standing seam or corregated metal?
 
It is standing seam. Great to hear that this is easy to do - whew... will talk to our builder and finalize that we WILL go through the roof ;-) I appreaciate all the insight here. It will be a loooong flue pipe but that will make for much better draw ;-)
 
It is standing seam. Great to hear that this is easy to do - whew... will talk to our builder and finalize that we WILL go through the roof ;-) I appreaciate all the insight here. It will be a loooong flue pipe but that will make for much better draw ;-)
How long?
 
Definitely plan on double-walled stove pipe to reduce cooling of the flue gases. On the roof, a metal-roof flashing looks like this. It's notched to clear the seams.
Excel metal roof flashing.jpg
metal roof install.jpeg
 
Thanks so much for this. Will look for a supplier for the flashing. I assume they come in various roof pitch or how are they adjusted? Our pitch is 10/12. Great information, esp. how the pipe is secured. Yes, we were going with double wall stove pipe...also to reduce soot in the house (cathedral ceiling).... Stove will go on the wall to the left of the patio door.

Great room .jpg
 
Without doing exact measurements - the flue pipe should be around 11 feet or so, the chinmey pipe around 10 feet..
Thats not overly tall at all
 
your primary source of heat should get primary consideration as to its location within your space, rather than as an afterthought location somewhere in a corner, or against a wall.

Chimneys exiting very near the roof peak are best. 1/2 way up the roof slope are marginal.

It's a new build. Put your radiant heater where its radiance will be most advantageous...

Or not.
 
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your primary source of heat should get primary consideration as to its location within your space, rather than as an afterthought location somewhere in a corner, or against a wall.

Chimneys exiting very near the roof peak are best. 1/2 way up the roof slope are marginal.

It's a new build. Put your radiant heater where its radiance will be most advantageous...

Or not.
Appreciate it!
 
Chimneys exiting very near the roof peak are best. 1/2 way up the roof slope are marginal.
Sort of, but that is more a case with short flues. I don't think it will be an issue here. FWIW, our chimney is halfway down the roof slope and 20' high. Draft has not been an issue.

Two things to plan on will be an outside air connection and one or two ceiling fans.