Woodburner has cracked existing fireplace and surround.

steampunkmimi

Hello. I wonder if anyone might be able to help/advise? Last November, we had a woodburning stove installed into our fireplace. It's a Stockton 7 inset, recommended by the installer. He said we didn't need a liner, and when we queried that, said it was because our chimney is already clay-lined, so doesn't need one.

Within a short time, we noticed cracks appearing in the pre-existing fireplace, and they've increased in size and number, all radiating our from the top right and left corners of the burner as we look at it. Installer insists it' all thermal expansion, and well within building regs. We're concerned that it may well be within regs now, but these cracks are increasing in size and number. Should he have installed a liner, or are we being overly cautious?

Thanks in advance.

Robwiz

My initial thought is that a liner wouldn't have made any difference. They are stainless steel, so will heat up and conduct heat very effectively and the inside of your chimney would be much the same temperature once the fire is going anyway. It's probably something in the construction which would have happened regardless of the fire and flue lining.

muckybutt

Ditto - the liner wouldn't make any difference.

steampunkmimi

Thanks for the replies. It's all a bit odd, because the other people who've been out to check the installation told us they wouldn't have installed without a liner, and the neighbour's installer was also quite surprised that our installer didn't use a liner. Still others have told us that they don't always install liners, but that if we'd queried it witht he installer, we should have been offered one anyway (a liner, that is).

I'm wondering why there's such a disparity... even friends of ours, who heat their house, business (a B&B) and obtain dhw from their burners, are adamant that they'd turn away any installer who didn't want to install a liner as part of the installation.

Greenfires

Haha - you'll find that installers simply can't win! If they insist on a liner they're always "ripping me off 'cos there's nowt wrong with my chimney" ("Me" of course ALWAYS knows much better than the bloke who deals with chimneys for a living) And now it seems if they don't insist on one, they're not doing the job properly!

In the real world, there are plenty of chimneys that are perfectly sound where a liner isn't an absolute necessity - clay lined ones like yours are often good - assuming the sections are fitted the right way up - which isn't always the case! In unlined (ie plain brick) chimneys, there are a number of advantages to using a liner, and a number of potential problems that can be avoided by using one - though the only time they really must be used is if the chimney is leaking. Boiler stoves are always a lot harder on a chimney so a liner is often recommended in that case.

Installers find that a lot of people want a job doing on the cheap - and as I said, the customer always knows best. Some fitters need the work and will play along, and some will refuse to carry out what they see as a sub standard job. The reason for that is that when the customer who insisted on cutting corners runs into problems a few years down the line - THEN it becomes the fault of the "bloody stove fitter doing a crap job"

Can't win!

rustyboy21

What is your fireplace made out of. Is there anyway you can post a pic or give a link without the www. in front and someone may be able to link to it.


If it is made of marble, then it will happen. You cannot regulate fully the heat output of a stove and as marble is full of hairline cracks ( that's what veins are ) it will happen. IMO liner or no liner, doesn't make a difference, it is what the heat from the stove is doing which is causing the issues.

Ectophile

Stainless steel flue liners aren't free. They cost money to buy and fit, so a liner would bump up the overall cost of the install.

My chimney doesn't have a liner - just the clay tiles it was built with. The owner of the fireplace show-room didn't think I needed a liner. The HETAS-registered installer didn't think I needed one either, and the registered chimney sweep who has swept it since is happy with it as well.

I do have some hairline cracks above the fireplace. Stoves put out a fierce heat, and that will cause everything to expand and contract each time the stove is used.

greyteam1959

And some stove manufacturers actually recommend you use a liner whatever the state of your chimney.
Clearview for one.....

steampunkmimi

Briefly: we were adamant that we wanted the job doing properly, and if that meant installing a liner, we weren't willing to cut corners to save a few pounds (we were apparently one of a few customers who'd asked why a liner wasn't recommended in our cases). The installer insisted we didn't need one, but didn't explain that the existing fireplace would crack. The lintel they've inserted the stove under is cracking, and this is something we're particularly concerned about. Lintels are supposed to be load-bearing, are they not? I'll try to obtain some photos.

ETA: Bricks and mortar.. the fireplace is bricks and mortar. Ectoplasm... thanks for that.

John_the_Boy

I also have a Stockton 7 inset and have noticed some hairline cracks in the plaster board above the mantelshelf. As said above just due to expansion and contraction. I also have a liner, didn't need one but thought it a sensible investment. Don't think you have anything to worry about unless you have bricks/stone cracking.

steampunkmimi

Not the first time we've noticed odd smells from ours, but it's been lit for over an hour now, is well into good burning temperature, and there's a noticeable smell of smoke/woodsmoke in the sitting room (where the fire is). Previously, we've noticed smells of the metallic variety (almost like solder) at a normal, steady burn, but this is definite woodsmoke. I thought that a properly installed woodburner shouldn't give off any smells at all, so what's this about?