Flue/Chimney leaking into loft

[Big G]

Hi

Just had two gas fitters around to fit a new fire surround and gas fire. They’ve tested the flue with a smoke bomb, checked the bedroom, checked the loft and have advised that the flue is leaking into the loft – “couldn’t see your chimney, your loft was so full of smoke” were his words.

Anyhow, he said that we could get a flue liner put in (£350 – standard 3 bed 1934 semi) but there was a problem. We have a hipped roof, a conservatory on the back and a bay on the front (of which we’re not sure how strong the roof is – it has shown signs of leaking in the past). This meant that putting ladders up may pose a problem.

I asked whether it would be possible to re-point the chimney within the loft – he suggested getting it rendered but said he couldn’t give a 100% guarantee that this would work. He’s left some smoke bombs should we want to get the work done and do some confidence testing before he returns to do the installation.

I’m fairly sure that the actual chimney isn’t blocked at the top. I didn’t see the smoke coming out of the chimney as I was at work – my missus did all the talking with the fitter (other than a phone conversation that I had). However, until very recently, we have used a gas fire and we haven’t keeled over yet!

I know that the rules of the forum state that I can’t ask how much a flue liner would cost to install but £350 seems steep to me. The shop where I bought the fire/surround from will take a cut no-doubt. If I get a builder in to do the work who can get past the bay, do I need to ensure he/she has any particular qualifications? Alternatively, is it worth going down the re-pointing route?


Many thanks in advance

G

 

[ollski]

I would get a builder in as I would imagine if fumes are leaking into the loft that the mortar must be in a right old state and the liner won't prevent the chimney collapsing.

 

[Nige F]

www.chimney-problems.co.uk

 

[Gasguru]

Many years ago I installed a 150mm liner in a friends 3 story coach house with tall chimneys. It took all day. Removing the exisiting pot, cleaning up the stack, getting the liner down was very difficult, I stood on top of the stack feet either side (in the pouring rain and wind) trying to get the liner down. I had two others in the living room tugging on the rope.

Assuming a 125mm liner, support plates and terminal may well a £100. Working off ladders is not easy and breaches safety regs, a scaffold may be required £250 for two people for perhaps a days work at heights seems reasonable to me.

I have tried dealing with CICO before - its a franchise setup and I was not impressed. There are better systems available that maintain the flue cross sectional area - but they may prove to be very expensive.

I would consider rendering the stack in the roofspace as unsatisfactory, if the pointing is that bad it probably leaks through the mid-feathers into the other flueway.

 

[ChrisR]

They should have tested the chimney before going to fit the fire. For a new fire it's (arguably) advisable to have it swept - which is your case would probably have brought down a load of mortar and pointers to trouble.

The sweeping would also give a good idea whether the liner installation was going to be difficult or not.
The one time I had a liner put in for me (roofer plus his oik took about half an hour to replace an existing old one) they charged £65, including benching-in the terminal on top.

You might consider a flueless gas fire. They cost more but are very efficient. They typically look like flued gas fires.

 

[Nige F]

Interesting point Gasguru....seemed like a good idea

 

[Gasguru]

The better systems use a motorised chain flail head to clean up the old lining and a spray applied sealant. Flue csa is maintained http://www.thermocrete.com/the_sealant_system.htm

I have a customer that was worried by their DFE fire and asked me to carry out a service.

The property is listed with very tall decorative stacks capped with a non-approved terminal and no ventillation provided.

The smoke test was inconclusive and the fire spilled big time even after 10 minutes on full power and a window open. The fireplace opening was the correct size and it should have pulled without any problem.

In the end I put the camera up the flue, it was standard 9x9 brick up to roof level. At that point chicken wire had been fitted across the flue and a 100mm liner was visible.

Concrete or other such material had then been poured around the liner to backfill up to the top of the stack. Up in the loft you could see where they had cut into the flue to fit the chicken wire.

This work was done apparently to strenthen the stack, unfortunately it made the fire lethal and the customer had the good sense to get further advice rather than using it. A DFE requires a 175mm flue, no terminal necessary (>170mm) never a 100mm liner.

Since the property is listed no vents were allowed. An illegal fire installation coupled with incompetant flue lining - a disaster waiting to happen.

Disconneted fire and a dissapointed (but alive) customer.

Don't cut corners.

 

[croydoncorgi]

There's another proprietary chimney-lining system based on pulling up a squidgy plug from the bottom with liquid sealant / render poured down on top of it. Seen it done a couple of times - seems to work.

But does require good access to the top of the chimney.

 

[Agile]

Back to the original posters question!

The problem is access to the chimney to fit the flue liner. I would have thought that £350 inc is quite reasonable.

In theory the CORGI is meant to do the flue liner AND TERMINAL himself but not many like working at heights and builders/roofers are often used under his direction from a safe ground level.

I did see a van once in London for a firm that specialised in flues and chimneys which was CORGI and looked quite professional.

Tony

 

[fitz1]

if u render chimney it only seals one quarter of your chimney.plaster could be haddled and between ceiling and floor joists could be leaking.

 

[Big G]

Here’s a few pictures of the chimney. I’ve done a smoke test (9:30 p.m. tonight as opposed to 11 a.m. this morning). Whilst there was some smoke - there wasn’t loads; but the chimney isn’t right.

Anyhow, I’m not worried about the structure/stability of the chimney. Just to decide whether re-pointing would suffice or whether to stick a liner in. Have thought about a flue-less fire but there doesn’t seem to be much choice.

From what has been said, £350 doesn’t seem too bad for a liner. Just need to see whether the roof is accessible. I’ll supply an outside photo tomorrow.


G

First picture shows chimney structure

This shows a spillage mark

This one shows that you can see into the chimney - I'm assuming the blue is the smoke