Proposed stove/flue/reline install

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Dmcqb

New Member
Nov 29, 2020
20
Wellsboro, PA
Attached is a diagram of my proposed stove installation. The brick wall, foundation wall, chimney and terracotta are all already there. I need to install the liner, tee, adapter(?), stovepipe, stove and hearth.

One of my constraints is that the existing chimney is 24” deep into the wall and my chimney is 17’ tall. Also, the existing breakout is only 14” from the ceiling. In order to meet the requirements that the chimney have 8’ in height for every one foot in horizontal run, and 18” clearance from the ceiling, I propose to have the stovepipe and chimney liner run at a 30° angle from the vertical stovepipe on top of the stove to the snout. This reduces the horizontal run significantly, as well as increases the clearance from the ceiling.

Questions:
1. Angle of joints in liner: I have seen comments that 45° joints are not permitted in chimneys, but 30° is ok within the chimney. Can someone confirm. I think 30° might be better anyway given the size of my existing opening (if I went to 45° I would have to knock out more bricks and cinders, or have a longer horizontal run). Is there evidence that draft on a 30° run would be significanlty better than 45°?

2. SS liner through cinderblock: Can someone confirm rigid 304L or 316L chimney liner should be used to pass from the tee through the cinder block and brick.

3. Chimney adapter: Can someone also confirm that a chimney adapter is required between the chimney liner and the stovepipe. The whole thing is non-combustible, but I've read elsewhere that there are concerns about overheating the blocks.

4. 1/4" blanket insulation: I propose to insulate the tee, tee snout and chimney liner that passes through the brick and cinder block with multi-layer quarter inch blanket insulation (will wrap at least twice, up to 4 times). Can someone confirm this works. (I want to use quarter inch because I will buy 25' of this for my SS flex liner and will have plenty left over. I plan to double-wrap. I need quarter-inch because I am running 6" SS through a 7" ID terracotta and don't have enough room for half-inch).

5. 60° stovepipe elbows: I have not seen 60° stovepipe elbows available for sail online. I only see 45 and 30. Any thoughts?

6. Finishing adapter at 30° angle from wall: Thoughts on how I finish the chimney adapter if it is sticking out at a 30° angle from the brick wall protection? I have searched but haven’t found products online. Wondering if I would have to try to weld sheet metal together to create a custom solution, but I have never welded before, so that isn’t optimal.

stove scheme bright.jpeg opening.jpeg
 
Last edited:

begreen

Mooderator
Staff member
Nov 18, 2005
89,791
South Puget Sound, WA
What is the ID of the flue where the ss liner will be installed? If 7x11 you may need to install an insulated oval liner like DuraLiner.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,791
South Puget Sound, WA
7" round.
I think you are going to have a very tough time pulling a 6" liner down that flue if insulated. Preinsulated 6" r has a 7.25" diameter.
 

Dmcqb

New Member
Nov 29, 2020
20
Wellsboro, PA
Was thinking I would do double wrapped quarter inch blanket insulation (but no overlap). If that doesn't fit, I'll just do quarter inch blanket with the recommended 3" overlap.
 

Dmcqb

New Member
Nov 29, 2020
20
Wellsboro, PA
I think you are going to have a very tough time pulling a 6" liner down that flue if insulated. Preinsulated 6" r has a 7.25" diameter.
Do you have another recommendation? Are you thinking I really need to get that terracotta out? Or should I just plan on quarter-inch wrapped once with a bit of overlap?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,667
central pa
Do you have another recommendation? Are you thinking I really need to get that terracotta out? Or should I just plan on quarter-inch wrapped once with a bit of overlap?
You won't get round liners out. Breakers don't work. What is the actual I'd of the clay? Do you have any joints that are offset?
 

Dmcqb

New Member
Nov 29, 2020
20
Wellsboro, PA
You won't get round liners out. Breakers don't work. What is the actual I'd of the clay? Do you have any joints that are offset?
7 1/8" ID for the clay. There are some offset joints.

Thinking I might just try to insulate the top 3-5 feet with quarter inch blanket, so at least there is some seal, and then wrap some extra insulation around the tee at the bottom, where I can reach it better.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,667
central pa
7 1/8" ID for the clay. There are some offset joints.

Thinking I might just try to insulate the top 3-5 feet with quarter inch blanket, so at least there is some seal, and then wrap some extra insulation around the tee at the bottom, where I can reach it better.
Do you have the required clearance to combustibles from the outside of the masonry structure?
 

Dmcqb

New Member
Nov 29, 2020
20
Wellsboro, PA
Is there a way to give credit to the insulation provided by the terracotta when calculating clearances?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,667
central pa
Is there a way to give credit to the insulation provided by the terracotta when calculating clearances?
Terracotta has very little insulation value so no. And the required clearances were determined for terracotta lined chimneys anyway.
 

Dmcqb

New Member
Nov 29, 2020
20
Wellsboro, PA
Terracotta has very little insulation value so no. And the required clearances were determined for terracotta lined chimneys anyway.
Amazing how one simple answer can change things. Thanks for prompting me to measure this more carefully!
 

Dmcqb

New Member
Nov 29, 2020
20
Wellsboro, PA
Update: I was able to smash out the 7" round terracotta liner with the Tile Breaker and 5' extension rods from Northline. I had read many concerns that it was very difficult to smash out a round terracotta chimney liner and was worried about unknown concrete crowns, but it went down without a hitch. I have a bit of extra equipment, but I will be able to use the extension rods to clean the chimney in the future. I smashed it out from the top down. Feeling very grateful.

I'll use a rigid 304 liner from Rockford for the new setup.

Thanks for the responses and cautions. You guys made my house a lot safer.
 
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bholler

Chimney sweep
Staff member
Jan 14, 2014
25,667
central pa
Update: I was able to smash out the 7" round terracotta liner with the Tile Breaker and 5' extension rods from Northline. I had read many concerns that it was very difficult to smash out a round terracotta chimney liner and was worried about unknown concrete crowns, but it went down without a hitch. I have a bit of extra equipment, but I will be able to use the extension rods to clean the chimney in the future. I smashed it out from the top down. Feeling very grateful.

I'll use a rigid 304 liner from Rockford for the new setup.

Thanks for the responses and cautions. You guys made my house a lot safer.
That's great. I have never had any luck breaking out a round liner. I am glad it worked out for you
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,667
central pa
Got any pictures from the tile breaking? Curious to see how thick that terracotta liner was to be able to be broken.
Thick terracotta can be broken pretty easily. The issue is the shape. In a round liner the breaker usually just spins without really impacting the liner
 

Dmcqb

New Member
Nov 29, 2020
20
Wellsboro, PA
Sorry, no video. I wish I had in retrospect. It was cool process. Seemed like standard 1/2" thick terracotta.

Maybe beginner's luck? I attached the tile breaker and rods to an 10 amp rotary hammer. If I tried to break more than 2-3" at a time it would just spin, but if I kept it at 2" at a time and gave the drill time to get up to full speed, it would reliably break it out. A few extra amps might have made the difference?

Also, it wasn't the ball-type breaker, but a 4x4" piece of square steel and the torque lock connected to it slightly off-center to make the spinning motion more random.