The Importance of Flue Lining in Your Chimney.

Chimneys are an integral part of most home heating systems. A masonry chimney is composed of several components, each playing an important role in the performance and function of the chimney, regardless of the fuel utilized or the heating appliance that is used. One of the most important, and perhaps least understood, of these is the flue lining.

A flue lining of a chimney is defined as "A clay, cast concrete or metal conduit installed in a chimney, intended to contain the combustion products, direct them to the outside atmosphere, and protect the chimney walls from heat and corrosion." A wise homeowner will want to know about the condition of the chimney, including the flue lining, in the home he/she owns or plans to buy.

If the chimney is unlined, has not built to Building Regulations or has been damaged in a chimney fire, flue gases can leak during use of the heating system. One of the primary functions of the flue lining is to contain these products of combustion. When a flue lining is cracked, these cracks open during the heating phase and may allow gases to pass to the chimney walls. These gases, being acidic, attack the masonry and will shorten the life of the masonry structure. In addition this can lead to carbon monoxide in the residence. Heat can be transferred to the vulnerable chimney walls. One of important functions of the flue lining is to serve as an insulator between the hot flue gases and the chimney wall. When the chimney walls are overheated, this heat can also transfer to surrounding combustibles.

If your chimney has suffered a chimney fire and is damaged, you are entitled to make a claim on your household insurance policy. Once the claim has been received, your insurance company will appoint a loss adjuster. Please be advised that the loss adjuster works for the insurance company and will try to limit the claim as much as possible. If you want to use your own loss assessor, you will have to pay for this yourself. The loss adjuster may require proof of a claim and will ask you to get the chimney CCTV surveyed by a chimney relining specialist.

Some insurance companies have their own "chimney specialists or experts" this in my opinion is a complete conflict of interests. Please be advised you do not have to accept their opinion especially if they do not inspect the chimney with a CCTV camera.

We at Cowan Chimney Solutions carry out a full CCTV chimney survey and inspection. First we sweep the chimney to remove any loose deposits to ensure full visibility for the CCTV camera.

We then carry out a full room, attic and roof inspection to see what damage (if any) has occurred.

We document everything in our report and forward same to the loss adjuster with a quotation for remedial works.

Now this is where the problems arise with some chimney relining companies.

According to Building Regulations 1997 Technical Guidance Document J-Heat Producing Appliances.

Size of Flues:" An open fire requires a minimum flue size of 194mm or 8 inches."

Some chimney relining companies are simply pushing a 6 inch or 7 inch stainless steel flexible liner down the existing 8 inch flue. This is not only against the above Building Regulations, but it is extremely dangerous i.e. if there's been a chimney fire and creosote is still residing in the 8 inch flue, pushing a smaller liner down this existing one will simply cause the creosote in situ to reignite, causing yet another chimney fire. The only way to fit an 8 inch liner is to remove all the existing clay liners. Beware of chimney relining companies who state that they do not need to open any holes in walls.

Scaffolding must be employed if working over 1 metre. Some chimney relining companies do not use scaffolding only ladders as it makes their quotation for remedial works cheaper. Beware of relining companies not employing scaffolding, if there is an accident they could sue you.

Chimney relining companies must use skips to remove all waste, they are not allowed to take the waste away in their vans as this is against waste disposal legislation.

Why do some chimney relining companies not comply with the above regulations?

Because it's cheaper and it only takes a couple of hours, not days to reline a chimney the wrong way.