Garage Chimney Repairs & Planning Ahead

[bholler]

On the other hand, had I not spent any of that, I would have still spent $5050 on other work done by the Mason and had zero ability to burn anything.

You still don't have that ability. You don't have a chimney with a properly installed code compliant liner. Also looking at your pics again it looks like your chimney doesn't even meet minimum height requirements with reference to the roof. So if you want to use it it will need extended to 2 feet above anything within 10 feet. Is the chimney inside the garage or outside?

 

[bholler]

“It’s a waste of money” says you.

How much does the average person spend on installing a chimney liner?

“Doesn’t meet code”
This whole install will not meet code because it’s a garage. The garage is too close to the property line to make it official living space. The only thing I can do to make this possibly meet code would likely involve removing the garage door, finishing all the walls so it looks like interior space, removing any chemicals and gasoline cans, making it so a vehicle could never be parked in there, and then hoping that someone would provide me with some government-approved (I.e. “nanny state”) stamp that tells me that my installation that has two stainless steel liners is less safe than one (potentially torn insulation) insulated liner install would be safer than what I’ve done.

Do you REALLY think that hiring some big company chimney company with some low level installer would really report back that he thinks he may have ripped the insulation where the liner enters the smaller neck of the chimney where it crosses the floor where the wood comes closest to the hottest elements? I highly doubt it. I would expect that the insulation would tear, and either nobody would know or they’d hide it from me to get paid and get out. I also expect I would likely pay something closer to $5000 for that type of job. I also wouldn’t be able to justify it, meaning, it wouldn’t happen.

Yeah, if I hired a company that was large enough to do the work, I’d always have the recourse of suing them if there was ever a fire. That’s not what I’m after though.

And if I need to make sure my “chimney” is at least 1” from any combustibles, my “chimney” is now effectively a double-wall 8” stainless liner that is surrounded in ~3” of brick. If I need to add 1/4-3/4” of insulation around the 6” liner, because I have the 8” smooth-wall liner, it won’t be too hard to make that happen now.

I will be sure to read this now before I report back here. https://codes.iccsafe.org/content/IRC2018/chapter-10-chimneys-and-fireplaces

Ok, you are talking to someone who personally installs on average one liner every week and has done so for about 12 years now. If the inside of your chimney is that rough I would just use pre insulated. But I really doubt it would be an issue with a properly wrapped liner using the mesh as required.

 

[stoveliker]

Methinks we can stick a fork in this one.
We may not agree on the best course of action, but the situation (chimney) is what it is now, and any more work than preserving cap and masonry is not needed at this time. I.e. this whole thing can be mothballed now until a stove is being installed.

 

[mnowaczyk]

You still don't have that ability. You don't have a chimney with a properly installed code compliant liner. Also looking at your pics again it looks like your chimney doesn't even meet minimum height requirements with reference to the roof. So if you want to use it it will need extended to 2 feet above anything within 10 feet. Is the chimney inside the garage or outside?

3 walls inside the garage. Exterior wall of the garage is the same as the back side of the chimney (under the roof).

 

[mnowaczyk]

Ok, you are talking to someone who personally installs on average one liner every week and has done so for about 12 years now. If the inside of your chimney is that rough I would just use pre insulated. But I really doubt it would be an issue with a properly wrapped liner using the mesh as required.

And the price tag would be?

And I believe no contractor is going to get on another contractor’s scaffolding.

So worst case, I may have wasted $1000. Right?

 

[mnowaczyk]

Methinks we can stick a fork in this one.
We may not agree on the best course of action, but the situation (chimney) is what it is now, and any more work than preserving cap and masonry is not needed at this time. I.e. this whole thing can be mothballed now until a stove is being installed.

I agree. Nothing is going to change until stove install time. The scaffolding is out of my yard, and I can get to the top of the chimney with an extension ladder when needed, but I hope that’s not too often.


I still need to read the code to understand why insulation would be required. My belief is that it’s probably to keep chimney liners away from combustible materials, especially in scenarios where youve got stock frame houses with framed in chimneys, but I need to read to understand.

 

[mnowaczyk]

And to show you what I needed to address. I didn’t anticipate ALL the stucco coming off.

 

[mnowaczyk]

You still don't have that ability. You don't have a chimney with a properly installed code compliant liner. Also looking at your pics again it looks like your chimney doesn't even meet minimum height requirements with reference to the roof. So if you want to use it it will need extended to 2 feet above anything within 10 feet. Is the chimney inside the garage or outside?

You say I still don’t have the ability. I think you are thinking of all this in terms of code as opposed to far more basic safety. Running a fire in an unlined brick chimney is far less safe than running a fire in the same chimney that has not just one, but two layers of stainless steel liners.

So I agree that I don’t have the ability to to run a fire in a code compliant way in this garage. I don’t believe that in the garage’s current condition, regardless of the chimney, would I ever be able to run a fire in a code compliant way. You can’t have a wood burning device in a garage. Period. Correct?

As I believe I answered above, 3 walls completely inside the garage until it gets to the roof line.

Regarding the height, it may be hard to measure at this point. I guess with a garage that not much more than 20 feet wide the chimney must be within 10 feet of the peak, but it is worth noting that it has the jerkin-head peak that does, at least on average, reduce the healthy closest to the chimney.

These pictures make it pretty clear that the original (or 3 weeks ago) height of the chimney certainly was not 2 feet above the peak. Also, I’m confident that it wasn’t much more than a foot that was added. The clay liner at the top that sits on top of the old brick is probably about a foot tall though. Add the 9” cap, and maybe that could give me the 2 feet required. I doubt it works that way though.

As for “code compliance”, I think finding the appropriate inspector (or at least a chimney sweep) to take a look at the complete setup and either give it a stamp of approval or “caution. Do not use.” Is what I will be looking for once I’ve got it all setup.

Hopefully there’s not too much more to spend on this one. Only time will tell.

I got most of what I wanted though, mostly didn’t get what I wanted with the 90 bend of the 6” liner at the bottom, but again, did t see the benefit in arguing too much with the Mason on that small item.

 

[kborndale]

I agree. Nothing is going to change until stove install time. The scaffolding is out of my yard, and I can get to the top of the chimney with an extension ladder when needed, but I hope that’s not too often.


I still need to read the code to understand why insulation would be required. My belief is that it’s probably to keep chimney liners away from combustible materials, especially in scenarios where youve got stock frame houses with framed in chimneys, but I need to read to understand.

The code is for under normal conditions pyrolis can occur which would slowly lower the combustion point of combustible materials. The other reason is for abnormal conditions like if you have a chimney fire.

 

[bholler]

3 walls inside the garage. Exterior wall of the garage is the same as the back side of the chimney (under the roof).

Ok in that case it needs 2" clearance to combustibles not 1"

 

[bigealta]

When i worked on a construction site many years ago and asked a question about how to do some framing nailing they said,
"Why are you asking me, you are gonna do it the way you want anyway".

 

[mnowaczyk]

8" is not big enough for an open fireplace and you really can't just add an open fireplace to an existing chimney anyway

You need to maintain a ratio of 10 to one between the opening of the fireplace to the size of the flue. With a rumford you can bump that down a little bit. But the construction of an open fireplace into an existing chimney will be very difficult

Apparently 10:1 is for square chimney liners and 12:1 is for round. 8” round supposedly 50 square inches. So the maximum fireplace opening would be 600 square inches. The fireplace in my house is 37” wide by 30” tall, 1110 square inches. So clearly a standard fireplace does require twice what an 8” round flue could handle. There’s a chart that makes it look like maybe the 22’ of rise I’ve got would actually enable a slightly larger than 600 square inch fireplace opening, but I think it’s negligible. But if the number is 625, then I could do a 25x25” fireplace opening.

I think there are different side openings allowed for Rumford Fireplaces. I will look that up. EDIT: Nope. That’s only about the depth being allowed to be as shallow as 12” and not less than 1/3rd the width instead of a minimum of 24” deep.

Ok in that case it needs 2" clearance to combustibles not 1"

or insulation it seems (to meet that UL 1777). Right?

 

[mnowaczyk]

It sounds like I will be pulling the 6” liner back out and insulating it. I read the instructions for the 6” liner I bought which is UL 1777 when installed with insulation (in my scenario).

I believe I read that some type of blocking near wood might be an option.

I would like to learn the R value of the insulation that’s used on chimney liners and also learn if there is any R value in the 8” liner I installed.

I still think that insulation would need one hell of a jacket in order to not shred to pieces going down my brick chimney with chunks of mortar and ribs of terracotta block stabbing into the insulation on its way down. That’s why I think the 8” smooth wall liner is a win for my scenario, even if I remove the 6” to insulate it and put it back in.

 

[mnowaczyk]

There appear to be some exceptions for flooring which is the combustible materiel closest to the chimney that might be at least 8” from the liner in most cases. Since the chimney is ~24x30 at the top, with an 8” liner, that leaves 16” to be divided among the two sides. So it sounds like maybe I just need to cut the floor and ceiling away from the chimney a little bit.

My Mason said that there is a steel lentil in the chimney where it passes through the floor / ceiling. So it sounds like it’s possible there’s no wood framing near the chimney that was apparently once used with no liner at all. There’s a hatch I was able to pry open in the floor if the second floor over a year ago. I may be able to open that up and determine if there is any wood framing anywhere near the chimney. Perhaps all I have to worry about is the wood flooring and ceiling on the first floor. I will check it out and report back.

 

[mnowaczyk]

No luck seeing any steel beams around the chimney. Everything is blocked off with 4x8s. So it seems that there’s going to be wood within 8” of the liner(s). I might have about an inch of clearance I could create around the chimney, plus up to 4” for the brick and mortar and then 1/4” inch of the 8” liner, but that’s only 5.25” if you don’t count the 8” liner as a liner. Sure MAYBE there’s another inch gap inside the 8” liner before you get to the 6” liner, but with all that, max would be 6.25”.

So the only way I see to have this meet the 2018 code is to add insulation to the 6” liner (and make this not a garage, and probably add height to the chimney too). It’s just not going to meet code any way I see it without spending tens of thousands of dollars. It just doesn’t seem worth it. So, yeah, I probably wasted a lot of money.

 

[bholler]

insulation it seems (to meet that UL 1777). Right?

Correct

 

[bholler]

No luck seeing any steel beams around the chimney. Everything is blocked off with 4x8s. So it seems that there’s going to be wood within 8” of the liner(s). I might have about an inch of clearance I could create around the chimney, plus up to 4” for the brick and mortar and then 1/4” inch of the 8” liner, but that’s only 5.25” if you don’t count the 8” liner as a liner. Sure MAYBE there’s another inch gap inside the 8” liner before you get to the 6” liner, but with all that, max would be 6.25”.

So the only way I see to have this meet the 2018 code is to add insulation to the 6” liner (and make this not a garage, and probably add height to the chimney too). It’s just not going to meet code any way I see it without spending tens of thousands of dollars. It just doesn’t seem worth it. So, yeah, I probably wasted a lot of money.

Yes with insulation and making it not a garage. Maybe add height those pictures looked closer than what I previously thought. The chimney and stove install would meet code. Assuming the stove is installed correctly and you add the tee.

 

[mnowaczyk]

Yes with insulation and making it not a garage. Maybe add height those pictures looked closer than what I previously thought. The chimney and stove install would meet code. Assuming the stove is installed correctly and you add the tee.

Here’s a height picture from about the same height as the chimney cap. It looks like if you could count the cap, then it would get the 2 foot requirement, but I don’t think it works that way. I assume it’s from the Terra cotta liner height which would be my max.

 

[bholler]

Here’s a height picture from about the same height as the chimney cap. It looks like if you could count the cap, then it would get the 2 foot requirement, but I don’t think it works that way. I assume it’s from the Terra cotta liner height which would be my max.
View attachment 328449

It's the liner exit that matters. That doesn't look like much of an issue if at all