Do I really need a stainless flue liner for a woodburner?

Hodmedod.one

Well-Known Member
After living 20 years in a house with 3 fireplaces I finally got around to thinking about installing a woodburner.

The house was built in 1994 and the inglenook that I want to use is fitted with a 225mm/ 9 inch clay flue pipe. The pipe sections are installed the correct way around (female end uppermost). The stove has a 150mm / 6 inch outlet.

So far I have visited 4 woodburner dealers.

2 of them have told me that I definitely need a stainless flue liner. They are quoting between £1000 - £1800 to install the liner and stove.

This in in addition to the cost of the stove which is £1000.

The other 2 shops are saying that the clay liner itself will be fine so installation will only be around £400 - £500.

I don't want tar and gunge dripping out from around the register plate but also I don't want to pay over £1000 more for something I might not need.

Either 2 are cowboys or the other 2 are trying to rip me off.

Advice please!
 
You don't need a liner if yours is intact . Ours is years old but sound and is easy to sweep , which isn't often as I mostly burn hardwood properly seasoned.
 
You do not definitely need a liner, but a professional chimney sweep will sweep, survey and smoke test your existing flue for about £60 - £80.

Then you can make an informed decision.
 
Just installed my own flue liner, not too tricky if the chimney is fairly straight and you have a roof ladder, but you need building control signoff. Theres a useful website called something like Stovefitter which has links to all the regs.
You are rihht you may not need a liner but just a register plate and stove pipe but whatever you do ut needs building control or hetas sign off or you wont be insured.
 
Echo the chimney sweep. They know their stuff and often hetas registered and could fit it for you if you need. If you have a liner it is safer burning softwood and crappy old offcuts with paint on too
 
The fireplace has never had a fire in it since the house was built in '94 so the clay pipe should be as good as new.
 
A pal of mine has i think 3 full lengths of stainless flow for a wood burner might even be a rear tar catcher bottom bit ! for sale, if you wish me to find out cost etc drop me a pm feller
 
After living 20 years in a house with 3 fireplaces I finally got around to thinking about installing a woodburner.

The house was built in 1994 and the inglenook that I want to use is fitted with a 225mm/ 9 inch clay flue pipe. The pipe sections are installed the correct way around (female end uppermost). The stove has a 150mm / 6 inch outlet.

So far I have visited 4 woodburner dealers.

2 of them have told me that I definitely need a stainless flue liner. They are quoting between £1000 - £1800 to install the liner and stove.

This in in addition to the cost of the stove which is £1000.

The other 2 shops are saying that the clay liner itself will be fine so installation will only be around £400 - £500.

I don't want tar and gunge dripping out from around the register plate but also I don't want to pay over £1000 more for something I might not need.

Either 2 are cowboys or the other 2 are trying to rip me off.

Advice please!


If it has been insulated your existing liner sounds fine, I had to enquire into this before we went over to woodburning for all our DHW/CH/Cooking requirements. If it is not insulated you may get condensate and draught problems. Problems with tar etc. are a sign of improperly seasoned wood, we aim for a moisture content of 11% - 16 %. We never burn coal on our wood burners.

atb Tim
 
For what its worth, I was in a similar situation a few years ago. I had the option of liner or use the existing clay. I chose to use the existing clay. Three years later no problems. The liner route after pricing it isn't that expensive if you can do it yourself. Enjoy your stove!
 
A little birdy told me recently some insurance companies won't pay out if a fire was caused by not having a bs standard liner ,don't know how true this is .my mate a retained fireman has been to plenty of chimney fires and thatch fires caused by no proper liner :(
Norma
 
A little birdy told me recently some insurance companies won't pay out if a fire was caused by not having a bs standard liner ,don't know how true this is .my mate a retained fireman has been to plenty of chimney fires and thatch fires caused by no proper liner :(
Norma

I suspect you have hit the Nail on the head here. What does your Insurance Company expect to be in place?

Yorkie.
 
In 1994 you would have had Building control. The clay liner will be perfectly good for the job, as previously said you would only get tar weeping through if you had a poor liner and you burnt unseasoned wood. Anybody fitting a woodburner should be registered and will fit a CO2 detector as part of the regulations.
 
Interesting thread. We had two wood burners, one with, one without. One without was horrible to regulate at low level and dreadful with certain winds. It now has a liner and pulls like a train.
 
Most wood burners have a certain sized flue. If your chimney flue is larger and you just shove the flue from the burner through a register plate and into the chimney flue you may have a gap for tar and sparks to fall down onto.
for instance a 6" flue into a 7" chimney.
this is where your liner comes in. 902 quality steel liner 6"dropped down into a tapered bracket into the 5" burner flue provides one continuous pipe to the top of the chimney from the burner.
 
It's not just about heat and fire risk. You need to view a woodburner as a gas appliance. You only burn wood at the start of the burning period, the heat of the stove then cooks the wood and gasifies it - so you are actually burning wood-gas not wood.

With an SS liner there is a far reduced chance of gas leakage into the other rooms of the house or back into the main room. This is why you must have a CO detector in the room with the burner to get building control to sign it off.

The stove is at it's most dangerous as it goes out (which takes 6 hours... in a small stove). The stove during this period is emitting gas, but won't have the heat to fully burn those gases, some of which are poisonous (CO just being the most fashionable). Leaks in any connection to the burner box can then leak that gas into the room and if the chimney is unlined (or has a cracked clay liner) into other rooms in your house (or your neighbours' in a terrace, flat or semi).

If you get away without an SS liner then make sure you have CO detectors in the rooms through which the chimnmey passes. You'll also need to religiously keep your liner in good nick.

All in all an SS liner is safer, will actually give a better draw and a cleaner burn and give you a known fixed cost. It is also more likely to be signed off without quibble.

Don't skimp, get a good quality one, or you'll have to replace it due to corrosion.
 
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been in building for most of my 65 years a well build flue with clay liner is designed for a coal/wood fire if installed correctly should be ok if you want belt and braces get it smoke tested. one thing I have found is that 7 or 9 inch dia flues can cause too much draw on a woodburner I would be advising a flue flap on the steel flue connection to adjust up draught in the flue.
 
hi hodmedod.one you have an old cast in situ liner made of clay by the sound of it. and it is large enough for your stove,. most stoves have a top diameter of 5,6, 7,8 inch rule of thum is say 6 inch of stove and a 6 inch liner. in your case 6inch to 9inch which is good. now you do not want to put a liner in as above.. CAUTION PLEASE GET A SMOKE SOUND TEST DONE. this is not the same as a smoke test. SMOKE SOUND TEST is having your liner from the top of the pot to bottom of your existing fire place filled with smoke, the idea is that you can then check for leeks in the upper rooms and the attic space, youse a good torch to look for the smoke. if indeed you do not have leeks then you can assume that your cast in situ liner is fine and install your stove,. as for your tar and gunge if you make sure that the flue is swept proper and that your registration plate is well fitted and flaunched well then no prob. ps if you do put a stainless liner down then use a 904-904 flexi approx cost per meter £30. and use vermiculite to insulate round the 904 904. you can pm me for further help if you want. member of institute of chimney sweeps. david
 
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hi hodmedod.one you have an old cast in situ liner made of clay by the sound of it. and it is large enough for your stove,. most stoves have a top diameter of 5,6, 7,8 inch rule of thum is say 6 inch of stove and a 6 inch liner. in your case 6inch to 9inch which is good. now you do not want to put a liner in as above.. CAUTION PLEASE GET A SMOKE SOUND TEST DONE. this is not the same as a smoke test. SMOKE SOUND TEST is having your liner from the top of the pot to bottom of your existing fire place filled with smoke, the idea is that you can then check for leeks in the upper rooms and the attic space, youse a good torch to look for the smoke. if indeed you do not have leeks then you can assume that your cast in situ liner is fine and install your stove,. as for your tar and gunge if you make sure that the flue is swept proper and that your registration plate is well fitted and flaunched well then no prob. ps if you do put a stainless liner down then use a 904-904 flexi approx cost per meter £30. and use vermiculite to insulate round the 904 904. you can pm me for further help if you want. member of institute of chimney sweeps. david
My boss put the vermiculite around all the flues on properties on the farm if I remember right stops warm air meeting cold and a moisture build up ?
Norma
 
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