installing log burner

[Staffbull]

Hi, I need to install a log burner into an existing chimney - question I have is what distance from the walls of the chimney do I need the burner to be, i.e. the air gap. I know bigger is better regards it ( ooh er missus) but what is the absolute minimum? Also does the liner need to be wrapped in insulation or will it be OK as is considering its been a chimney for 50 years. Reason i want to fit one is I am getting fumes when lighting a fire in the "small living room" to the large living room next door. We have a fire in one but not the other, I think the chimney has broken down somewhere inside :-( My thinking is if its sealed from the burner to the chimney pot its going to be no more leaks :-)

I have googled away on this and cant come up with anything.

[Tim Watts]

About 50mm absolute minimum. Usually this is covered in some depth by the manufacturer's installation instructions - can you download a copy from their website?

Ultimately, if the surrounds are clear of combustible materials for >300mm, ie the stove is going next to masonry, nothing bad is going to happen, but the fire may give less heat than hoped for as a large proportion comes of by convection and the rest by radiation.

The liner usually does not have to be insulated if it is not going anywhere near combustibles - subject to possibly some other constraints, such as being able to manage an adequate draw.

You would be best to quot your parameters here (stove size (physical and kW), opening size and height of chimney.

Or you could ring a HETAS installer if you are not doing a DIY job and check the stove is suitable before buying.

[Staffbull]

Thanks Tim, its a small room 12 x 12 current opening is 16" grate so a small burner will do fine, one issue is the chimney has a 45 degree bend immedialtly after the top of the opening, but ive seen flue pipes with 45 degree bends on ebay so these should do. Chimney is 30ft high opening to pot. It will all be DIY

[Staffbull]

I'm looking at this one as its seems tof it a 16" opening

[Tim Watts]

A flexible liner will go round a 45 degree offset bend - I have the same. The installer did have a little bit of a fight though...

If it's DIY - technically it is a notifiable job (to buiding control).

I would advise you to read the manufacturer's installation instructions and the relevant section of the building regulations though - they should intersect on the key points and the building regs will fill in the gaps.

They's all online if you google search.

Check the regs also with respect to air provision - my HETAS installer told me he wanted to see a new air vent appear in the room, so I put one in meeting his requirements before he came.

Smoke pellets/matches would be a good idea to test it with too and a CO alarm in the same room is always a good idea (if you do it OK now, the flue

*might* get blocked for some reason later).

I'm not really an expert - but I did read through the building regs to make sure I set the job up right for the HETAS installer (the air vent was borderline, but he wnated one, I was happy to take his learned advice).

Wait around and see if anyone else has anything to say.

Are you familiar with the ways to do the flue connections, sealants etc?

[andrew]

'm 3 years out of date now but essentially you need a 150mm flue, air provision if over 5kW and the distances are in the document.

If there is a break down between flues then you need a new liner and this needs to be certified with a tag/plate.

AJH

[Staffbull]

Thanks - the 4kw seems to be the smallest anyone does. And seems to fit a 16" opening - the liners are double skinned from what I make out ans cost more than the stove !!

[PeterC]

In a canal-side pub I was looking through a magazine about narrow boats and there were several ads. for wood-burning stoves. They were made to fit in small spaces and, I would guess, take only small logs. Didn't need much flue, either!

[geraldthehamster]

What's the difference between "notifiable" and "technically notifiable"? ;-)

Seriously though, I've always taken a "realistic" attitude to whether to bother involving Building Control with my various works, but if I were buying a house and a stove had recently been installed, with the theoretical capacity to suffocate me or burn down my house, it's one thing I would* want to see a certificate for.

Cheers Richard

[Tim..]

Thanks - the 4kw seems to be the smallest anyone does. And seems to fit a 16" opening - the liners are double skinned from what I make out ans cost more than the stove !!

Correct!! If you said the woodburner itself was circa £1000, then the liner, cowl, stove pipe and sundries would be approx a further £1000 installed.

Do not skimp on the liner, use a quality 904/904 insulated twin wall flexi and fill the chimney itself with vermiculite from the top. It's important that the flue is insulated otherwise you will have issues lighting the thing due to lack of draw. Doing so will also solve the danger of flue gases escaping through brickwork etc into an upstairs room if the flue ruptures which is a HETAS requirement, which in itself is an insurance requirement.

If the stove is over 5kw you must have a supplimentary airsupply, usually I core drill to outside behind the stove, therefore no cold draughts.

Tim..

[tinnews]

A CO alarm is mandatory with any sort of solid fuel burner now I believe.

[tinnews]

Yes, that's the normal cost proportions, the flue/liner costs at least as much if not more than the stove.

[Staffbull]

Been thinking about this some more, the smoke through in the other lounge has only started since I got a cap fitted to the pot for the other lounge on the stack. We were having smoke blown down this chimney so got the sweep to fit a brewer ufo anti smoke cowl to the pot for this grate, at the same time he fitted a rain cover on the other pot so effectively shutting it off. My thoughts now are both flues may converge at the top? and therefore since next room grate is blocked off at the top its cauing some smoke to come back down into the the room? I may try getting the sweep to fit another ufo style cowl to the other pot as it will give the flue a chance to flow.

Thoughts anyone please? or is it just a waste of =A350 for the cowl? if it does work its going to save =A31000 though, and before christams that would be good !