Install a liner in a chimney with brick and mortar in the way

[Dave A.]

No chimney expert, But I would think the best way to repair it would be to open the outside of the chimney in the problem area, if possible.

 

[frankinri]

No chimney expert, But I would think the best way to repair it would be to open the outside of the chimney in the problem area, if possible.

Trying to avoid that. This area is covered in flashing. I think I'm gonna use a sawzall or grinder to get it down. If I end up with a hole from removal of brick I will just fill the space with hydraulic cement. I like the rebar with a sharp edge or a pool cleaning pole with a cold chisel on the end to reach the mortar sticking out.

 

[frankinri]

I'm trying hard to figure out WTH the mason was thinking when he did that.

Me to. Ran out of blocks, lol

 

[CenterTree]

I got up on the roof today to inspect the chimney for the install of a flexible liner. What I found was a clay lined chimney 7 inches. This is good because I need to install a 6 inch liner.

Are you planning to wrap the liner with insulation? If so, you will have a tight fit in that 7 inch clay.
Figure a 6inch liner can be 6.25 OD.(if smooth wall). Your insul wrap will need 1inch. (half inch x 2 )

Now you have 7.25 inch. (or more)

Also you will have the wire mesh wrapping and some clamps. Tight I think. Just a heads up.

 

[frankinri]

Are you planning to wrap the liner with insulation? If so, you will have a tight fit in that 7 inch clay.
Figure a 6inch liner can be 6.25 OD.(if smooth wall). Your insul wrap will need 1inch. (half inch x 2 )

Now you have 7.25 inch. (or more)

Also you will have the wire mesh wrapping and some clamps. Tight I think. Just a heads up.

I was not planning on insulation. I didn't think it was necessary being inside an existing chimney. Am I missing something on this? Also the stove englander nc30 calls for a 6 inch minimum. Because of this I don't feel comfortable going with anything smaller than that. From what I understand it will create smoke in the room or backdraft if the pipe is under 6.

 

[altmartion]

I was not planning on insulation. I didn't think it was necessary being inside an existing chimney. Am I missing something on this? Also the stove englander nc30 calls for a 6 inch minimum. Because of this I don't feel comfortable going with anything smaller than that. From what I understand it will create smoke in the room or backdraft if the pipe is under 6.

I would recommend insulation. you don't want condensation. it will rot the hx from the inside out. does it give specs on chimney height? these people who had backdaft, did they use insulated liner or un insulated?

 

[frankinri]

I would recommend insulation. you don't want condensation. it will rot the hx from the inside out. does it give specs on chimney height? these people who had backdaft, did they use insulated liner or un insulated?

What is hx? I'm looking at the manual for the stove on their website. This is where is see the 6 inch minimum and the implications of being bigger and smaller than that. My height will be just under 20 feet. Here is the link to the manual

http://www.englanderstoves.com/manuals/30-NC.pdf

 

[altmartion]

if you can make the 3', 2', 10' rule you generally will be fine. the hx is the heat exchanger. I takes a lot more energy to heat and maintain a 7" concrete and clay chimney than it does a 6" insulated liner. you will get better draft sooner, especially in the shoulder season.

 

[Nick Mystic]

I've been studying your photos and can't figure out what or why that obstruction is sticking out into the flue. It looks as though it was deliberately put there when the chimney was constructed and that would make me nervous about busting it out with a chisel, etc. until I understood its function. I'm guessing once you bust it out you will have a much bigger job repairing the liner/chimney if it turns out there was a good reason for why it was there. Any time you start hammering on masonry work you run the risk of loosening up other joints in the structure that could damage the integrity. If you are determined to try removing this obstruction, that you think is brick, I'd consider using a carbide bit in a hammer drill. A 3/8" bit should be able to drill through the brick. This would accomplish a couple of things. One, you would verify what you're removing by seeing what is being drilled out. Second, if you only drilled some holes every half inch or so it would make it that much easier with your chisel idea and perhaps limit how much hard pounding it will take.

 

[frankinri]

if you can make the 3', 2', 10' rule you generally will be fine. the hx is the heat exchanger. I takes a lot more energy to heat and maintain a 7" concrete and clay chimney than it does a 6" insulated liner. you will get better draft sooner, especially in the shoulder season.

Can you elaborate a bit on this 3 2 10 rule
And where the heat exchanger is sorry I just don't understand. Also if condensation forms in the liner wanted just fall to the bottom of the liner?

 

[frankinri]

I've been studying your photos and can't figure out what or why that obstruction is sticking out into the flue. It looks as though it was deliberately put there when the chimney was constructed and that would make me nervous about busting it out with a chisel, etc. until I understood its function. I'm guessing once you bust it out you will have a much bigger job repairing the liner/chimney if it turns out there was a good reason for why it was there. Any time you start hammering on masonry work you run the risk of loosening up other joints in the structure that could damage the integrity. If you are determined to try removing this obstruction, that you think is brick, I'd consider using a carbide bit in a hammer drill. A 3/8" bit should be able to drill through the brick. This would accomplish a couple of things. One, you would verify what you're removing by seeing what is being drilled out. Second, if you only drilled some holes every half inch or so it would make it that much easier with your chisel idea and perhaps limit how much hard pounding it will take.

Good point thanks for the idea. I will try this.

 

[altmartion]

I've been studying your photos and can't figure out what or why that obstruction is sticking out into the flue. It looks as though it was deliberately put there when the chimney was constructed and that would make me nervous about busting it out with a chisel, etc. until I understood its function. I'm guessing once you bust it out you will have a much bigger job repairing the liner/chimney if it turns out there was a good reason for why it was there. Any time you start hammering on masonry work you run the risk of loosening up other joints in the structure that could damage the integrity. If you are determined to try removing this obstruction, that you think is brick, I'd consider using a carbide bit in a hammer drill. A 3/8" bit should be able to drill through the brick. This would accomplish a couple of things. One, you would verify what you're removing by seeing what is being drilled out. Second, if you only drilled some holes every half inch or so it would make it that much easier with your chisel idea and perhaps limit how much hard pounding it will take.

and this is why I suggest securing the tile before removing the obstruction. I have seen pieces of flat stock steel in between liner sections. these are the reasons your should always run a "pig" through the chimney from top to bottom.

 

[altmartion]

Can you elaborate a bit on this 3 2 10 rule
And where the heat exchanger is sorry I just don't understand. Also if condensation forms in the liner wanted just fall to the bottom of the liner?

your pipe should extend 3 feet above the roof penetration , and be at least 2 feet above the highest point and must have 10 feet radius of clearance from any obstruction

 

[frankinri]

and this is why I suggest securing the tile before removing the obstruction. I have seen pieces of flat stock steel in between liner sections. these are the reasons your should always run a "pig" through the chimney from top to bottom.

Boy am I the new guy on the block what is the pig?

 

[frankinri]

your pipe should extend 3 feet above the roof penetration , and be at least 2 feet above the highest point and must have 10 feet radius of clearance from any obstruction

I'm good on all of these except the 2 ft above the highest point. The chimney comes out onto the roof but not at the peak. From the front of the house you can even see the Chimney the peak Is the highest point.

 

[tickbitty]

How far down is that brick? Wonder if you could line it just up to that point and leave it unlined for the final 5 feet or whatever that is. I know we are all in favor of lined chimneys here but there are plenty of "slammer" installs still around and lots of newer installs where they just put the liner up past the smoke shelf and let it go up on it's own from there. If this offending brick is 5 feet or less from the top, you could consider leaving it there and sending the liner up from the bottom? It just looks like a very large section of brick, would hate to see you do major damage to your chimney because of busting it out!

 

[Nick Mystic]

tickbitty,
If he ran the liner up to the bottom of that protruding brick and stopped there it seems like the creosote that builds up in the chimney for the final few feet to the top would end up dropping down the chimney outside the flex liner. Eventually he would have to probably pull the insert to clean that mess out since it doesn't seem like a good idea to just let it accumulate on top of the block off plate or on top of the insert if he doesn't go with a block off plate. I have a Woodstock Classic in the lower level of my house that is connected to a clay tile liner through a wall thimble. The flue continues down inside the large chimney for about 18" beyond the thimble so when I pull my single wall stove pipe between the stove and the thimble for cleaning I also remove all the debris that is in the bottom of the clay flue in those final 18". I can tell you there is a sizable amount of creosote debris ( 2 - 4 cups in a season) and I'm burning very dry wood and burning with the cat engaged.

 

[CenterTree]

I was not planning on insulation. I didn't think it was necessary being inside an existing chimney. Am I missing something on this? Also the stove englander nc30 calls for a 6 inch minimum. Because of this I don't feel comfortable going with anything smaller than that. From what I understand it will create smoke in the room or backdraft if the pipe is under 6.

I have not suggested to go any smaller than 6 inches. I am just informing you that if you insulate (and you most likely SHOULD) you may have a really tight fit in that 7 inch clay.

Insulation will keep your flue hotter so that the burnt gasses can exit the top before they cool and condense (and cause creosote).

Also, insulation will give you better safety from heat.

I believe a lot of liners are tested to UL specs WITH insulation. So without the insulation, you may fall short of being UL listed.

Good luck getting that brick out. Hope it goes well.

 

[altmartion]

How far down is that brick? Wonder if you could line it just up to that point and leave it unlined for the final 5 feet or whatever that is. I know we are all in favor of lined chimneys here but there are plenty of "slammer" installs still around and lots of newer installs where they just put the liner up past the smoke shelf and let it go up on it's own from there. If this offending brick is 5 feet or less from the top, you could consider leaving it there and sending the liner up from the bottom? It just looks like a very large section of brick, would hate to see you do major damage to your chimney because of busting it out!

that is a good question. I am not sure it would work because the masonry part I don't think will get the necessary draft with the metal liner being used . up to that part will be full of cold air and will effect draft. I guess if nothing else worked he could try to put in a "block off " plate just below the liner term and hard pipe the last little bit. I would treat this as a last resort tactic. I am not even sure it would work.

 

[KaptJaq]

Once the brick is gone and the 6" liner is installed you should have no problem with a 20' internal masonry chimney. If it was an external chimney I would suggest insulation. If you do have drafting problems with the un-insulated chimney you can always use pour-in insulation after the fact.

Your concern now is the brick and mortar. Lining part way up is not a good idea. Cresote will get between the liner and the old flue. Cleaning will be tough. I am more partial to cutting the brick than smashing it out. You do not want to weaken anything else with a lot of hammering. The motar that squeezed in betwen the joints usually comes off with a few light taps. I used a shash weight on a chain to get rid of one that was blocking my flue.

KaptJaq

 

[altmartion]

Boy am I the new guy on the block what is the pig?

lol. it's just something made for checking for obstructions in objects. it's like the test cone you would use to check a chimney in preparation for a liner, which is what really should have said. I use "pigs" when I do large plumbing jobs with very long runs after I have backfilled. usually when I do camp ground or something of that size. it confirms that nothing like junk in the line or crushed or kinked line or anything will obstruct the pipe, or what ever it may be.

 

[12pack]

geez,

just give it two whacks with the sharpened piece of rebar and a lump hammer. Anybody ever do masonry? Thats how you cut a brick in half...with a hammer, not on a wetsaw, not with a grinder, not with a sawzall, and especially not drilling it, the guy cant reach it...lets not re-invent the wheel.

OK, let the flaming come my way, I'm ready and the vodka is flowing.

 

[begreen]

I'm good on all of these except the 2 ft above the highest point. The chimney comes out onto the roof but not at the peak. From the front of the house you can even see the Chimney the peak Is the highest point.

It just needs to be 2 ft higher than any building structure within a 10ft radius. If the peak or roof slope is further than 10ft away, don't worry about it.

 

[frankinri]

Lol 12 pack sounds like a plan. I gotta go get some rebar. One last thing how do you all recommend installing the hole for the stove in the basement? I have to cap to old holes ( on the wrong side) and make a new one.

 

[KaptJaq]

Looks like his last piece of tile liner was not long enough and he didn't have another. He used the bricks to space the liner up so the chimney would appear to be to code.

The reason I don't like whacking it with rebar or anything else is that it is sitting on the fragile clay liner. I would at least drill a couple of holes in it first to weaken it and guide the crack. You can use a masonry bit in a drill extender (http://www.amazon.com/Bosch-Daredevil-DSBE1012-12-Inch-Extension/dp/B002BYOWKM/ref=sr_1_1?ie=UTF8&qid=1386036741&sr=8-1&keywords=drill bit extender).

KaptJaq