Woohoo! Finally picked up a fireplace insert!

ADDvanced

Member
Dec 1, 2016
41
Milwaukee
From the manual:

"7. Minimum chimney size is 6" (152mm) diameter. Maintain a 15' (4.5m) minimum overall height measured from the base of the appliance. Chimneys should be inspected to check for deterioration and to determine if they meet the minimum requirements, and be upgraded if necessary. The chimney must extend at least 3' (914mm) above the roof and at least 2' (610mm) above the highest point within an area of 10' (3m) of the chimney."

If I measure to the base of the fireplace it's probably right aroung 14-15', as the unit is right around 2' tall.
 

kennyp2339

Minister of Fire
Feb 16, 2014
5,121
07462
This can go 1 or 2 ways, since the chimney is located in the center or near center of the house (not an outside wall) I'm assuming but would like you to confirm that its a minimum 2ft higher then the peak of the roof. If its to code with the minimum 2ft higher then the peak of the roof you can wing it, just buy the 6" insulated liner rated for solid fuel appliances.
But be advised, your right there with the minimum height, so if your experiencing poor draft, you may have to add a 3ft length of class A chimney pipe, this is done by removing the top chimney / liner cap and replacing it with an Class A anchor transition plate, then the class A pipe will click into that along with the cap to keep animals and weather out.
I'd make sure if you go route 1 and wing it on the draft to purposely leave 6" of extra liner hanging off the top off the chimney and not silicone glue the anchor plate for the liner down until all things are good to go, you don't want to have to splice your liner, especially once its installed in the chimney cause the insulation will rip as you pull it back out.
 

ADDvanced

Member
Dec 1, 2016
41
Milwaukee
My chimney... like the stone part with the concrete pad, is a good 3' above the peak of my roof. The terracotta liner extends up another foot, with the grate/raincap thing on top of that. Think I should still leave it hanging sideways?
 

begreen

Mooderator
Staff member
Nov 18, 2005
84,180
South Puget Sound, WA
Many SBI stoves tend to breathe fairly easily. I think you will be ok with the height. An insulated liner will help draft by keeping the flue gases hotter. As for the damper, you can either remove it or you can cut a notch in it so that the liner easily clears. Some prefer the latter because the notch could be filled with a welded-in plate at a later date if the desire is to return it to use as a fireplace.

Note that lower cost liners will be thinner, some can be poorly made. Regardless of choice it must be stainless and meant for wood. This is infrastructure, so it's not a bad place to pay a bit more for quality. Also, pay attention to the direction of installation so that it is not installed upside down. There are many places to order a shorter liner online. You will need more than just the liner. Rockford and others sell kits that are 15' and have the proper appliance adapter, top plate and cap.
 

begreen

Mooderator
Staff member
Nov 18, 2005
84,180
South Puget Sound, WA
The terracotta liner extends up another foot, with the grate/raincap thing on top of that. Think I should still leave it hanging sideways?
?? Can you post a picture of this?
 

kennyp2339

Minister of Fire
Feb 16, 2014
5,121
07462
My chimney... like the stone part with the concrete pad, is a good 3' above the peak of my roof. The terracotta liner extends up another foot, with the grate/raincap thing on top of that. Think I should still leave it hanging sideways?
No, just don't cut it flush with the terracotta for now, you can cut the insulation flush, leave a small hunk of liner beyond that though incase you need to add the class A pipe to make better draft, you'll know after running the stove for 2-3 weeks what your working with, draft is more finicky in warmer temps then cold temps, so if your drawing good with temps in the 40's then you'll do even better when it drops to the 20's & 30's. I just don't want to see you do the same work twice, a little extra with the rain cap down to the plate that goes over the terracotta will look fine for a few weeks, you can always go back up and button things up.
A good test of draft with a new stove is to first establish that you have dry firewood (seasoned to me is like salt and pepper, your little is my a lot) grab a moisture meter from mernards, split open a peice of firewood and test the new face by inserting (kind of firm) the prongs into the split, if your below 20%, your good to go,
Do your break in fires, read your manual first, but essentially you want to bring the stove temp up in incremental steps to cure the paint, during that time your going to smell paint and veg oil burning off both the stove and liner (coated in factory to keep from rusting while in storage)
As you do your break in fires you will start to get a handle on your draft, start ups might be sluggish, but as long as your not flooding the house with smoke while temps are in the 40's you should be good to go, after your 3rd break in is done, make a regular fire, let it get established, the turn the air to half way, after the fire is seated, slowly open the door, if you have good draft you shouldn't have any large puffs of smoke that come inside, if you do consistently get smoke inside the house when you open the door on an established fire, you try adding a 3ft length of cheap black pipe to the end of the chimney liner, if you see an improvement then you know to add the class a pipe. If there is no improvement, try cracking a window open near the insert, this will establish whether your fighting a negative draft issue or not, also make sure when opening the loading door that the bathroom fan, range hood or the dryer isn't, those are big air suckers.
 

begreen

Mooderator
Staff member
Nov 18, 2005
84,180
South Puget Sound, WA
The 6" kit from Menards is not a good fit for this installation. It has a tee which is not needed instead of an appliance adapter. It's also too long and has no insulation. Here is an example of a liner kit complete with insulation from Rockford -

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brenndatomu

Minister of Fire
Aug 21, 2013
5,349
NE Ohio

brenndatomu

Minister of Fire
Aug 21, 2013
5,349
NE Ohio
Isn't double walled the same as insulated?
Nope...and you don't want double wall liner...that stuff has issues. If you want heavy duty, get heavy duty, but not double wall... honestly single wall is fine ...just needs insulated.
Now when dealing with stove pipe, double wall is good...and class A chimney pipe is often double wall too ...or triple, but double is better for wood burning.
 

begreen

Mooderator
Staff member
Nov 18, 2005
84,180
South Puget Sound, WA
Isn't double walled the same as insulated?
It can be a little confusing. There is double-wall liner that is a 2 ply liner. This is not insulated and is not recommended. If you go to Rockford's site you will also see a preinsulated liner that has insulation between two walls. This is a different product.
 

BigJ273

Feeling the Heat
Feb 15, 2015
270
Maryland
Yes measure the inside dimensions of the flue.

Chimneys that are used for solid fuel burning are required to have clearance from the outside of the masonry structure to combustible materials. For an internal chimney that is 2" an external one needs 1". This is because masonry is very good at transferring heat. Over time with that wood being heated over and over the wood pyrolizes lowering the kindling point untill the heat transfer ignites it. If you don't have the required clearance you need extra room for insulation on the liner.
So, just curious. How does this apply to roofing materials?? Isn’t there always some type of roof deck, shingles, tar paper, etc hitting the masonry chimney somewhere along the roof line?
 

kennyp2339

Minister of Fire
Feb 16, 2014
5,121
07462
So, just curious. How does this apply to roofing materials?? Isn’t there always some type of roof deck, shingles, tar paper, etc hitting the masonry chimney somewhere along the roof line?
A 1" air space is still needed, thats why there's usually (2) layers of flashing, the first is more or less a long L shape (angled) that goes from the roof deck to along the chimney side, then as you install shingles your suppose to add step flashing along the way (this is how I did my chimney for the oil burner) I also think, but not 100% sure on it, but I think the code allows only the sheathing material to come in contact with the chimney, certainly no framing though, but I would check building codes on that.
 

BigJ273

Feeling the Heat
Feb 15, 2015
270
Maryland
I just have a very hard time believing masonry chimneys all have a one or two inch gap where no roofing/siding material is touching the brick. That’s a hard pill for me to swallow. And if u have an insulated stainless steel liner, inside of a clay liner, inside of a brick chimney, These clearances still apply??
 
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kennyp2339

Minister of Fire
Feb 16, 2014
5,121
07462
I just have a very hard time believing masonry chimneys all have a one or two inch gap where no roofing/siding material is touching the brick. That’s a hard pill for me to swallow. And if u have an insulated stainless steel liner, inside of a clay liner, inside of a brick chimney, These clearances still apply??
The insulated liner mitigates those clearance issues, upon closer inspection of the chimney rule, say you have a house with a chimney on the outside wall, 1" of air space is needed from the combustible flaming / ply wood, and as long as there is a minimum of 8" from the flue liner / tile you can abut siding material to the outside masonry chimney walls (ie corner of the cement block)
Its that 8" distance from the flue to the nearest combustible material and the 1" air gap between the outside block and the house structure that causes the issue, if you install an approved insulated liner then your adhering to the liner test specs and the clearances are then reduced making the bad chimney fall back within the good graces of code.
 
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begreen

Mooderator
Staff member
Nov 18, 2005
84,180
South Puget Sound, WA
I just have a very hard time believing masonry chimneys all have a one or two inch gap where no roofing/siding material is touching the brick. That’s a hard pill for me to swallow. And if u have an insulated stainless steel liner, inside of a clay liner, inside of a brick chimney, These clearances still apply??
In our house we had a more recently installed chimney for an oil furnace. This was done correctly and I suspect it was inspected. That chimney had the proper 2" clearance right up through the roof. I know because I removed this chimney when the house was raised. The old 1924 fireplace chimney touched wood in multiple locations.
 

BigJ273

Feeling the Heat
Feb 15, 2015
270
Maryland
Yea. I don’t know for sure what my house has as far as clearance, mainly because it’s already built and all buttoned up. It could be perfectly fine, and probably is built to code. I was just doing some thinking out loud. Our chimney is on an outside wall. I attached a pic to show where the siding/roofing materials abut the chimney. Our boiler is the flue on the left (square cap) and our wood stove liner (insulated stainless steel) is in the clay flue on the right (round cap) . Just to give u an idea
 

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ADDvanced

Member
Dec 1, 2016
41
Milwaukee
Idk what to tell you guys. If you google double walled chimney pipe, the internet says double walled = insulated, as there is an air gap. This air gap provides SOME insulation. It it as much insulation as a full wrap? Probably not. But I also have a chimney in the center of my house. Since it isn't exterior I wasn't sure I needed insulated anyway, so this is what I'll be using, along with a blockoff plate insulated w Rockwoll.

I had to buy 25' of rockwool insulation, so I could theoretically use some metal zip ties to strap some of that to the pipe as well, since I don't have much use for it other than the small amount I will use for the blockoff plate. Idk what else to do with this insulation, really. Is there any benefit to stuffing it behind the stove? Again, the chimney is sort of central to the house, so I'm assuming that insulation behind the stove would actually be bad, as it would prevent heat from radiating behind the chimney into the room behind it?
 
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brenndatomu

Minister of Fire
Aug 21, 2013
5,349
NE Ohio
Idk what to tell you guys. If you google double walled chimney pipe, the internet says double walled = insulated, as there is an air gap. This air gap provides SOME insulation. It it as much insulation as a full wrap? Probably not. But I also have a chimney in the center of my house. Since it isn't exterior I wasn't sure I needed insulated anyway, so this is what I'll be using, along with a blockoff plate insulated w Rockwoll. I had to buy 25' of rockwool insulation, so I could theoretically use some metal zip ties to strap some of that to the pipe as well, since I don't have much use for it other than the small amount I will use for the blockoff plate.
You are getting things confused.
Doublewalled chimney pipe (class A chimney) usually has insulation. (triple wall is usually air cooled)
Doublewalled stove pipe has an air gap, no insulation otherwise
Doublewalled flex liner is just two layers of metal, no gap, no insulation. Then there is also pre-insulated flex liner...it is double walled with insulation in between.
 

brenndatomu

Minister of Fire
Aug 21, 2013
5,349
NE Ohio

bholler

Chimney sweep
Staff member
Jan 14, 2014
22,100
central pa
I just have a very hard time believing masonry chimneys all have a one or two inch gap where no roofing/siding material is touching the brick. That’s a hard pill for me to swallow. And if u have an insulated stainless steel liner, inside of a clay liner, inside of a brick chimney, These clearances still apply??
They almost never have the required clearances which is why I always say people should always insulate their liners. Insulation negates those clearance requirements.