Chimney Linings - Help

[Anonymous]

I'm confused ....can anyone help.

We have in a 2 story Victorian Terrace in London and have had our chimney opened up and swept. It was bad enough choosing the stove - after much umming and ahhing I think we are going for a Dovre Wood Burning Stove (cleanburn so approved for use in smokeless zone)....but we could go for multifuel option instead if we wanted...or a Clearview...arrgggh don't set me off again!

Anyway...Initially I planned to get a flexible metal liner dropped down to line the flue, but since having a discussion with someone who works in the trade (did my sisters chimneys, but can't do the job for me as they are in Derbyshire), I have been discouraged because they say these liners can perish very quickly - within 2 or 3 years sometimes, due to the acidity of the fumes, and also can be damaged when swept once they get older etc. I do have a good chimney sweep so I'm fairly sure he'd use the right brushed and be careful. He said if only burning wood this wouldn't be so bad, but was still an issue to consider.

So, his advice was poured concrete....but then reading on here I saw that this can be an issue if pumped into an older house, and also that the chimney has to be opened up where there are bends to put spacers in - this really isn't an option for us - recently decorated, baby sleeps in room chimney passes through etc. etc. Anyway, so far I can't find anyone near London who offers this service.

I now feel so confused and a little discouraged by the whole thing. We can't afford to spend £1,000 on a liner only to have to replace in 3 or 4 years time.

Our stove will mostly only be used at weekends in winter, and sometimes throughout the week during very, very cold weather, or maybe next time I'm on maternity leave if off during the winter. But wouldn't be put to excessive use.

So, can anyone offer an opinion? Has anyone got a metal liner, and if so has it lasted well for you? I know one of the important things is to ensure the space around it is backfilled, so I will check they would do this, and what they would use.

Can anyone recommend any installers in the London area? I am currently planning on using the company I am buying the stove from - Kent Fireplace Company in Bromley.

Thanks so much for reading this, and for any advice.

Amanda

 

[Anonymous]

" I know one of the important things is to ensure the space around it is backfilled,"

Does this apply if it's only used as a flue for a gas boiler?

 

[Anonymous]

From what I've been reading, it's very important if burning wood in a stove because otherwise you can get condensation in the flue, which is not good.

 

[Anonymous]

Most liners will come with a guarantee either 10 or 20 years depending on the grade of the steel. Check how that works and what the conditions are with the supplier. If you are going to burn smokeless fuel you will want the 904 grade not the 316. Smokeless fuels are more corrosive apparently.

If you are going to do only occasional use then stick to wood and sweep a couple of times a year. You will need a 6" flue if you are going to do wood burning. If your stove is 5 inch then you get a 5" - 6" adapter either for the flue to stove pipe connection or in the stove pipe run.

Stricktly speaking a flexible flue does not have to be installed although they are recommended, have you had the existing chimney checked and inspected ? People do just put a closure plate at the bottom of the chimney with the stove pipe going through it.

filling in around a flexible liner is only for insulation purposes, it helps with the draw of the fire by minimising the coldness of the air column above the fire - debatable how essential this is - I stuffed a couple of the rockwool liners up from underneath and start the stove by burning a few crumpled sheets of newspaper to start off.

 

[Anonymous]

There have been a few posts on here in the past about concrete liners. The concensus seems to be dont do it. They can cause damp problems in the stack, and if they do leak (smoke) then you dont have the option of reversing it (like you do with a liner).

As posted above most liners should carry some sort of warranty. Also if you can get the fire burning nice and hot as quick as possible and always use nice dry fuel you should minimise the chances of corrosive tars in the smoke and maximise the life of your flu. I think you would need a crappy liner and to treat it very very badly in terms of wet fuel etc to get a life as short as 5 years...

G.

 

[Anonymous]

Far be it from me to incite anyone to act contrary to the our great god the Building Regulations, but I've been burning wood in woodstoves with the pipe stuffed a short way into the old chimney for thirty years. No linings, just the bare chimney as the bricklayers of old intended. I've had no trouble. I occasionally stick my brush up but there's never anything like the amount of soot that one gets with coal. A bit of brittle tarry stuff accumulates round the top of the metal flue pipe where it opens into the void and this needs knocking off every few months. Most of what I burn is pretty dry oak. Of course I lie awake each night waiting for the four horses of the apocalypse to charge down my chimney.

 

[Anonymous]

LOL Biff, I do totally take your point, and I know some people do choose to do it this way (was going to say choose to take the risk, but then the question arises IS it really a risk at all). The thing is that this chimney goes through my daughters bedroom, and given that I've read there is a risk, however small of toxins leaking through the brick and into the room, plus chimney fires I just don't feel I can take the chance...she is way too precious.

But I do know understand where you are coming from, honest......hope the horses continue to stay away!

Amanda

 

[Anonymous]

If the main worry is the chminey leaking into rooms you could always make use of a carbon monoxide detector. Even a flu lining or concrete tomb can leak so it's worthwhile whatever you choose.

Personally having looked into it, I will be using a flexible liner but not insulation and only burning well seasoned wood, some of which will be stacked next to the stove for an extra bit of drying prior to burning.

Also I suspect that a chimney cap (to keep rain from running down the flu) will help. My guess is that the tars need to be disolved in water to form an acid, so as long as the lining stays dry it will be fine.

G.

 

[Anonymous]

The chimney is there for the purpose for which it was built. If this is in good condition ,( have it checked). Keep things simple, it is usually cheaper and more efficient .
I share your concern, if the chimney is sound it will be fine.

Biff is right, our " modern" lot will have our ancestors turning in their grave.

 

[Anonymous]

Our ancient solid-fuel 4-oven Aga was brilliant at drying out wood. During the winter the two left-hand (cool) ovens were always stacked with the stuff.
I'm going positively misty-eyed at the memory.....

 

[Anonymous]

Stainless Steel flue liner has really come down in price recently and you can expect to pay around £20 per metre for the 316 grade which would probably be suitable for your requirements - obviously installation would be extra, but you should be able to find a selection of qualified fitters for stoves and flues at http://www.hetas.co.uk.
A liner will help improve the performance of the stove, but more importantly it improves safety. Mortar in older chimneys gradually deteriorates and what is a safe chimney now, may not be in a few years time.
The liner should have a good lifespan, the 316 grade usually has a 10 year guarantee providing it is fitted and used properly. Importantly make sure it is installed the right way up and do not clean it with metal brushes.
I realise it is usually an extra unseen cost and I would consider hard myself whether to reline a sound chimney, however you are looking to buy a decent stove and must be spending at least £650 on that, so it is probably worth doing the whole job properly and avoiding extra mess at a later date.

 

[Anonymous]

>The liner should have a good lifespan, the 316 grade usually has a 10 year guarantee providing it is fitted and used properly

Living in a house that has been here for 250 years (including chimneys) and seeing no reason why it shouldn't last another 250 (other than global warming induced sea level rise), I am a little underwhelmed when I read about 10 year guarantees.

 

[Anonymous]

Many thanks for taking the time to respond to my post. It has helped to reassure me and I feel I can make an informed choice now, which is the most important thing.

Amanda