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Discussion Starter #1
I am no stranger to building a basic 8" flue chimney, but almost all of my work is repair work, meaning I go tear down the 50 year old one and put up an identical one.

In that instance the siding has already been trimmed up to the chimney and the eaves cut out, I just have to build it plumb and flash it in.

On a new chimney installation on a house with wood siding should I remove the siding and put the chimney in the recess against the sheathing then trim around it, or should I just build it up off the wall and cut through the eave as necessary?

My first instinct says to build it as close to the wall as possible so I don't have any risk of the footer tipping, but my second instinct says that if I do my footer correctly and pin it to the existing foundation it shouldn't matter either way.

I just want to be prepared with an answer when the HO asks for my opinion, messing with the siding would probably raise the price a good deal since it is a lot of screwing around.
 

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Discussion Starter #2
I should have gotten more details first, I just found out the height of it.

Definitely going to need wall ties.

I am still curious for the sake of knowledge though, could you build a free standing chimney say under 20 ft without fear of the wind coming through and knocking it over?
 

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Have Trowel, Do travel
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why risk, with an overly adequate foundation pinned on the bottom and pulled from above, it can be done,
but why
 

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The footing needs to be 2x as big as the chimney, I would even go 3 feet by 3' with a crap ton of steel into the foundation. I usually have a pal of mine dig these out so its no biggie to make it over sized.

Cut the siding out adding a ground to each side, or whatever you want to use. Paper it before you put on the grounds. Caulk it unless its like a clear stain. Cut the roof out plumbing with a 4' level when you get the chimney near it. Best way for a wood hack like me to get a straight cut. Paper under the trim you remove, or rubber it if you have any of that kicking around.

Wall tie the piss out of those chimney block chimneys. I would even mention that the chimney wont last 10 years without a coating like California stucco or equivalent on it. Exposed blocks just dont do well. I suppose it could be a brick chimney, dunno.

Leave expansion for the flue as well.
 

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Just built one last week about 16' tall. I pinned to the existing foundation and wall ties about every other block. I ran straight up the wall which was brick and then vinyl above the eave line (this was on a gable end.)

One aspect I did not expect was the sheathing was built out a half inch behind the vinyl and I had to bump out the block a bit to clear the sheathing. I managed to keep a straight corner because I was holding the block out a bit anyway. If you put a 6' level on the outside you can see the taper out, but not with the eye.

Piece of cake I thought. Cut the eaves, box it in and add a bit of trim.:clap:
 

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My first instinct says to build it as close to the wall as possible so I don't have any risk of the footer tipping, but my second instinct says that if I do my footer correctly and pin it to the existing foundation it shouldn't matter either way.


The National code that governs in my area( N.W. Indiana) mandates that the masonry chimney have a 2" air space from combustibles. That means roof fraiming,sheating,soffit,facia.etc. I would look closely at your code before building it as close as possible to the wall.
 

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That code is relegated to interior chimneys here FJN and in 1 town around here only the throat section(including smoke chamber smart asses) should be built 1" away from the sidewalls while the brick facade is butt up against it.
 

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That code is relegated to interior chimneys here FJN and in 1 town around here only the throat section(including smoke chamber smart asses) should be built 1" away from the sidewalls while the brick facade is butt up against it.



You are correct,two inches interior,one inch exterior. Either way,the chimney can not be in direct contact with combustibles.
 

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My fireplaces dont work , I dont even have a flue, its capped off at the damper. All show no go.

Im with the govt. , I see what they want. People cannot have a way to burn wood to heat their house.

We must protect the public from these dangerous fireplaces that are burning down millions of homes every year.
 

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Discussion Starter #13
Went and looked at it, there was one there already, piece of cake again, tear down the old one and slap in a new one with new wall ties, footer is already in place. and no signs of movement.

The flue was crumbling and most of the block above the roofline was cracked, I would guess it's 40+ years old, he said it was old when they moved in.
 

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Nice, I usually get some bats or even those red squirrels behind almost everyone of those for some odd reason.
 

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Discussion Starter #15
I always get stupid pigeons for some reason, dead ones. They cram themselves in there and then get stuck and die or something.
 

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You are correct,two inches interior,one inch exterior. Either way,the chimney can not be in direct contact with combustibles.
It's the same thing here, and I even got called on it once by an inspector, at our cabin Up North............:whistling
 

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While I know that it is code I have yet to see a chimney that doesn't have j trim butted up against it...unless there are bricks on the rest of the house. Generally i only see the framing and sheathing kept away the 1"/2"
 

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While I know that it is code I have yet to see a chimney that doesn't have j trim butted up against it...unless there are bricks on the rest of the house. Generally i only see the framing and sheathing kept away the 1"/2"
If you put brick or stone on the chimney with the required 1" cavity behind it, you're legal. In my scenario, I ran the 16" chimney block right tight to the sheathing, which a big "no-no".......
 

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When I build decks around chimneys I'm required to keep framing 2" away from the outside. Always thought this was stupid, if it's going to get that hot we have a safety problem other then the deck.
 

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Discussion Starter #20
When I build decks around chimneys I'm required to keep framing 2" away from the outside. Always thought this was stupid, if it's going to get that hot we have a safety problem other then the deck.
That is stupid.

Any chimney with a good flue in it should be cool enough to touch provided they are burning the stove properly.

If that thing is getting hot enough to ignite sheathing I doubt that extra 1" is gonna help.
 
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