Hi all still debating on my future plans of two new stoves at my house. I'm almost set and ready for my living room stove/liner combo. Now couple questions regarding basement stove. The existing clay flue is in the same masonry a fructose as my upstairs stove.. Yes two separate. Now I was wondering on the specs. The down stairs is 30 ft top to bottom. It is also a smaller diameter clay flue. I'm not 100% on size right now. But I am wondering if I should step it down to a 5" ss liner? Also I know there are issues with bare ss liner touching the existing clay but is there any issue with the insulation wrap touching. I can foresee myself having to force the 5-6" ss liner down the clay flue after wrapping it with the kit. Thanks again!
Liner touching clay?
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webbie
Seasoned Moderator
Actually, there are probably rarely issues with either the insulation or a round pipe touching the clay inside wall of a chimney. Let me explain....
The UL tests are usually done on unlined chimneys where wood is virtually touching the masonry (brick or block). They are also done indoors and often in the worst possible conditions (painting surfaces black, etc.)
In a decently built masonry chimney which meets modern codes, it's even possible to burn without installing a ss liner - especially if the size of the masonry flue tile is relatively small. In that case, you have more flexibility in the choice of and installation of a liner since you are not using it to brig a totally defective chimney up to code, but just for ease of cleaning and an extra measure of safety.
Personally, if I thought the chimney was in pretty good shape, I'd rather have a non or barely insulated 6" than a 5" - but, it also depends on the stove. There is also 5.5" liner available which may fit the bill.
The UL tests are usually done on unlined chimneys where wood is virtually touching the masonry (brick or block). They are also done indoors and often in the worst possible conditions (painting surfaces black, etc.)
In a decently built masonry chimney which meets modern codes, it's even possible to burn without installing a ss liner - especially if the size of the masonry flue tile is relatively small. In that case, you have more flexibility in the choice of and installation of a liner since you are not using it to brig a totally defective chimney up to code, but just for ease of cleaning and an extra measure of safety.
Personally, if I thought the chimney was in pretty good shape, I'd rather have a non or barely insulated 6" than a 5" - but, it also depends on the stove. There is also 5.5" liner available which may fit the bill.
mellow
Resident Stove Connoisseur
If you have cracks in your clay then you need to insulate to meet code, insulation is fine to touch the clay. Next step is to measure that flue and inspect it, no need to jump ahead on size until you do that.
Nick Mystic
Minister of Fire
I wouldn't be concerned with the liner touching the clay tiles causing a problem with heat transferring to tile and heating it up. Rather, I'd be concerned about the clay tile liner cooling the ss flex liner at the point of contact causing the liner to cool down and get a build up of creosote at the point of contact. When I installed my ss flex liner I made my bottom connection to my T-connector and then pulled some slack out of the flex liner at the top of chimney before I tightened down my top plate clamp so that the liner would straighten up and pull away from the sides of the clay tile liner.
Thank you all! One less thing to worry about! I think on my basement stove I am going to hold off on insulating or adding an ss liner. The clay is in excellent condition I think basically I'm going to run a t- connection past my foundation. Wall to point the exhaust directly up I to the clay flue. Now my main floor I am going to be doing a full insulated liner next year once I decide on a new stove. Now another question is would you guys install your largest stove in your basement or on the main floor? I have a completely open floor a-framed house so tons of volume to heat upstairs. Friends suggest biggest stove I can get to be put in basement and still a medium large for upstairs. What would u do? Thanks again
mellow
Resident Stove Connoisseur
Not knowing the ID of that clay flue to the basement I will say that I burned into the 11" X 7" ID 30+ foot flue from my basement one season. Draft was pitiful and the next season it had a 5.5" liner in it and it was like I had bought a new stove. The draft and burns were so much better.
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webbie
Seasoned Moderator
I'm in agreement that even a decent tile lined chimney should be lined with SS - if for nothing else, for the better draft and the easier cleaning - let alone the extra safety factor. Exterior chimneys are really poor when 100% masonry....
As far as stoves, this depends on a lot of things - the layout of the house, size of the rooms and probably more importantly, the air flow. Sometimes heat will just stay in the basement, so a big stove will roast you without moving the heat up into the home! You will see a lot of people here saying that the heat won't move.....
Better to do more thinking and research before making the final decision.
As far as stoves, this depends on a lot of things - the layout of the house, size of the rooms and probably more importantly, the air flow. Sometimes heat will just stay in the basement, so a big stove will roast you without moving the heat up into the home! You will see a lot of people here saying that the heat won't move.....
Better to do more thinking and research before making the final decision.
For an A frame a ceiling fan or two is a necessity. A friend had a large A frame and we set him up with a PE T5. That worked ok but it was hot up on the 2nd floor. Then we put in the ceiling fan and it made a world of difference in evening out the heat.
PS: masonry a fructose? cell phone translation? lol
PS: masonry a fructose? cell phone translation? lol
Had one for 30 years and never had a problem cleaning it, it was a round one though.
When I looked into chimneys in 1980 the clay liner had a higher temp rating then the metal chimneys, has this changed?
webbie
Seasoned Moderator
I went down to the masonry yard a couple years ago to get some flue tiles for experiments with my chimney cap inventions.
It took a LOT of sorting to find some without cracks - brand new!
You are 100% correct that round flue tiles are better and it's possible to make very good ones. But the cheapo clay tiles were made square so they are easier to stack and we've had 50 years of folks not really using their fireplaces - so the quality and construction has suffered.
Products like the isokern are really top notch (insulated masonry) and a properly built masonry flue with a round tile and poured insulation could be pretty nifty - but the problem is that virtually NONE are built this way!
It's a lost art. Once in a while I hear of or see a good one in a house built to high standards in the 1910 to 1935 time frame. But most modern masonry chimneys I have laid eyes on don't measure up.
mellow
Resident Stove Connoisseur
Even if you find ones that are not cracked, trying to find a sober mason is the next huge challenge.
Thats funny, when I was a kid back in the 60's we had a mason in the small town I grew up in and he drank too much, I guess you never knew if he was going to finish a job or not.
That is identical to my basement stoves future setup... 30 ft 11x7 clay. Did your new 5.5" with insulation fit easily? Is a 5.5" to 6" adapter easy to find for a T connection?
No insulation. Fit great. Talk to the liner company about their availability of an adapter. A liner kit will have a 5.5" tee but the "snout" that goes through the wall will be six inch.
Just this weekend I had my 6x10 ID 42ft. internal clay lined flue chimney draft tested.
Low fire/flue temps (175 F tested with IR gun), .06-.08 w.c.
Regular fire/flue temps (275 F) .07-.10 w.c.
When tested with basement door open all #'s jumped .01-.02 w.c.
These test results put my draft at the high end as per Drolet. They claim anything over .10 w.c. could result in over fire and #'s at or below .30 w.c. would result in poor draft in their stoves.
Provided for information purposes only.
Low fire/flue temps (175 F tested with IR gun), .06-.08 w.c.
Regular fire/flue temps (275 F) .07-.10 w.c.
When tested with basement door open all #'s jumped .01-.02 w.c.
These test results put my draft at the high end as per Drolet. They claim anything over .10 w.c. could result in over fire and #'s at or below .30 w.c. would result in poor draft in their stoves.
Provided for information purposes only.
You think insulation would be an issue fitting down the 11x7? Also for the layout . The basement is open and half finished with drywall . The stair case upstairs has no wall blocking or doorway it is open up to the basement entrance which leads into our kitchen. The whole upstairs is completely open kitchen/dining/living room. So a ton of volume and yes I have a ceiling fan running clockwise right now. Gonna go with a larger span fan tho figure 52 inch to a 60-70 inch would help with circulation and keeping heat down with the wide open layout
I couldn't get six inch liners, which are 6 1/4" OD, down either chimney. I darn sure wouldn't have been able to get an insulated liner down them. Get a paint can, that is usually the same diameter as a six inch liner, and lower it on a rope and see what happens.
Have to weigh my options for basement but I will probably just T it off through the wall and dump right into 11x7 for awhile and with it being 30' height I may think about 5" liner. Or skip the insulation although I would like insulation since it is an exterior . Any more insight on basement having larger or smaller unit? With the way I described layout. I really want a long burn time in the basement but do t really want a cat stove down there. Any recommendations on largest free standing non cat under 1500$?
I have no recommendation. I have burned everything from a double barrel stove glowing red hot to cast iron stoves and a pellet stove down in that basement and it takes six hours just to start feeling a little heat coming upstairs since the walls and ground eat so many BTUs. And after that it isn't enough to heat the first floor much less both stories of this barn.
But into just those flue tiles your draft is not gonna be strong enough to realize the full potential of a EPA wood stove anyway. Just a fact of life verified dozens of times a year by new members here.
But into just those flue tiles your draft is not gonna be strong enough to realize the full potential of a EPA wood stove anyway. Just a fact of life verified dozens of times a year by new members here.
mellow
Resident Stove Connoisseur
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