How to fit a fireplace lintel
How to fit a fireplace lintel
5 mins

How to fit a fireplace lintel

Wood stove installer fitting a concrete lintel and adding mortar

Where is the lintel?

There should always be a lintel or arch above your fireplace/builder’s opening (to support the building material above your wood burning stove). Sometimes you discover that an errant builder forgot.

You can often find this lintel or arch by shining a torch inside your builder’s opening (assuming you have an opening or have started excavating) or removing plaster from the chimney breast or wall.

In many properties a lintel will be non-combustible (concrete/slate/granite etc.) but in some properties a lintel will be wooden.

Note that a wooden beam can present a serious fire risk: Distance to combustibles and heatshields.

If the present arch or lintel is too high then you will need to fit a new one underneath the existing one (if the higher one is wood then it may need to be removed: see Distance to combustibles and heat shields).

What do I need to do?

Fitting a lintel is an easy task

Buy a concrete lintel (usually 4″x3″x whatever length required). Cut it to length (ideally using a 9″-wheel angle grinder as a 115mm wheel will not quite get through) and ensure it is long enough to be well supported each end (4″ or 6″ overlap, see next paragraph). Please research the correct size lintel before choosing.

Make sure it is level using a spirit level (you may use the lintel to attach your closure plate or register plate to at a later stage and having it completely horizontal makes the job a lot simpler).

Warning

Make sure that you allow enough height for your hearth thickness plus the height of your wood burning stove plus 40cm (minimum). This will ensure that you have enough height above the stove to fit two flue-pipe elbows should you need to do this (due to your stove being too close to the back wall leaving insufficient air gap to cover the stove-manufacturer’s requirements).

Too little gap and the elbows will not pass the lintel or will pass through the register plate (closure plate) at 45 degrees which means you cannot use a sealing cover plate.

Diagram showing a wood stove in a fireplace recess using two elbows to move stove more into room

Lintel height

Two offsets can require 35cm or more, so please make sure your lintel is high enough.

Elbows-with-soot-doors require the most height (only needed if stove cannot be swept though the stove).

Adaptor should be above the closure/register plate.

A lintel that will end up 50cm+ above the top of the stove will give adequate clearance should it be necessar to have two elbows above the stove without the lintel being in the way.


15 or 30 or 45 degree elbows all can be chosen from depending on how much offset is required.

If you have between 35 and 50cm gap then this might still work but you’ll have to do lots of in-situ measuring (and do not forget the stove collar can be 0-15cm high).

Concrete lintels are cheap (under £10).

Adding a lintel

If you have discovered that there is no lintel in place or if you wish to add a lintel higher than the present one then you have to use common sense.

If the chimney breast is brick and the opening no wider than one metre then I am happy to breakout the fireplace and fit a new lintel without using acrow props. Any wider then I will use acrow props.

Here’s the proper way of fitting a lintel using acrow props: Fitting a lintel using acrow props (external site).

Warning: stone properties

I will never breakout a recess in a stone property if I have not found the lintel and will never move that lintel or put one higher. I will always employ an experienced builder.

Brick arch above wood burning stove

Moving a lintel

You might need to move your lintel higher due to adding a flue offset (as mentioned above). But you might find that this exposes the structural, interlocking brick “gather”.

The gather is structural (is holding up what is above it using interlocking brickwork) and must not be removed except by a builder who knows what she is doing.

Otherwise you can just live with the gather. It will make fitting a chimney-sealing closure register plate more difficult but it is all possible.

FAQs

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Costs correct as of April 2023:

Approx. costs if you have a chimney and fireplace ready to use: £750-£1,000 (save £500 by self-installing).

Approx. costs if you have a chimney but need the fireplace "opening up": £1,600-£2,200 (save £1200 by self-installing).

Approx. costs if you do not have a chimney and need a clip-together flue: Shed £475-£700. Bungalow £1500. 2-storey house £2500. Save £1,000-£1400 by self-installing.

Above figures include labour and materials but no appliance.

We, of course, advise you to purchase your stove and materials from Stovefitter's to ensure quality goods are installed (some installers use budget materials to increase margin). If you buy your stove from us (rather than your local small shop or installer) we have a lot more power when approaching manufacturer's with a warranty issue. Why is that? Because we buy many hundreds of stoves a year from these brands.

We do not fit stoves.

But we know a few who do!

Google: Hetas installers

Hetas are the trade body of registered UK installers.

Most installations will require that you slide a chimney liner down your chimney (flexible metal tube 5" or 6" in diameter). Do you have a narrow chimney and want to lessen the risk that a liner might not go down your chimney? Then make sure your chosen stove can use a 5" liner.

Must I line my chimney? Best read this article but most likely the answer is yes. Do I have to fit a chimney liner?

DEFRA-Exempt wood burning stoves with a 5″ collar can usually be fitted to a five inch liner rather than the usual 6″ minimum, making the installer's job much less stressful.

ALL OF THE 5KW STOVES WE SELL CAN BE FITTED TO A 5" CHIMNEY LINER.

I seriously suggest any self installer fits a 5" liner unless they know their chimney is large enough for a 6"!

What is the best chimney liner? Silvacore 904 (we sell it so of course we will say that ;-). What is the best chimney liner?

Will your stove require an air vent within the room (some stone walls are very difficult to drill)?

5kW or under and wood burning stoves often do not require an air vent (new builds always require an air vent).

What is the maximum output in kW of your "5kW" wood burning stove? The majority of manufacturers just specify the “nominal output” and this figure means very little in real life. The nominal is a figure the manufacturer chooses to sell the stove at - the stove is capable of reaching at least this output with one fuel load. Nominal means "capable of". But it is not the maximum.

Check out the size of the area where the logs will go (firebox size) as this varies enormously. The kW output is completely dependant on the amount of logs burning at any one time - more logs burning equals more heat. If you can fit three logs in stove A and just two logs in stove B then stove A will be capable of throwing out 33% more heat.

DO NOT TRUST MANUFACTURERS’ kW RATINGS as manufacturers specify what output they desire to sell the stove at and testing allows for much “playing with the figures”. This is why you can get very small 5kW stoves (e.g. Aga Little Wenlock) and very large 5kW stoves (e.g. DG Ivar 5 by Dik Geurts which is actually rated 5kW but has a MUCH larger firebox than the Ekol Crystal 5 by Ekol Stoves). A Crystal 5k might get to 5kW and not be capable of any higher whilst a DG Ivar, despite being rated at 5kW, can get to 8kW with a full fuel load.

Note that, over time, one might damage the internal firebricks of a stove by running at a higher load than the manufacturer's suggest. Firebricks are easily replaceable.

Will your wood burning stove fit in your recess WITH the required air gaps around it? This is obviously not an issue if your stove will be freestanding.

Air gaps to non-combustible materials (brick, stone etc.) are usually "as close as you like" legally but manufacturers will sometimes specify a recommendation. This recommendation is there to allow heat to escape from the recess into the room - so you get the heat benefit rather than the heat soaking into the building structure and being lost. If no gap to non-combustibles recommended then we suggest 50-100mm air gap left and right of stove, 50mm behind and 100mm above.

Are you in a Smoke Control Area (usually built up areas)?

Choose your stove accordingly.

A stove must be DEFRA-Approved if you wish to burn wood in a smoke control area.

ALL OF THE STOVES WE SELL ARE DEFRA APPROVED FOR SMOKE CONTROL AREAS.

In simple terms if a stove has an efficiency rating of 70% then 30% of the heat from your logs goes up the chimney.

If a stove has an efficiency rating of 90% then only 10% goes up the chimney.

So think of this in terms of how many logs you have to chop/buy.

Example: A Saltfire Peanut 5 by Saltfire Stoves in Dorset has an efficiciency of 80%.

A tall chimney (6m or more) that is lined will be happy with an efficient stove.

Efficiency importance can be said to be overrated and anything between 75% and 85% is fine. Go much higher and performance can actually suffer (smoke in room when opening door to reload, blackening of glass).

Many modern stoves can go on 12mm thick hearths. Others require full, 5″ thick constructional hearths. All of the stoves we sell state whether or not a 12mm hearth is suitable.More about hearths for wood stoves here.

Can you can talk to somebody on the phone should you need to after the wood burning stove has been delivered, especially if you are self installing? Will the staff at “wesellzillionsofstoves.com” be able to assist with any installation issues? What if there are any problems after install?

Do yourself a favour before ordering stoves or materials on the Internet: Go to Trustpilot and type in the company name before you buy. Some companies advertising at the top of search engines are not good news - check for yourself.

When striving to find thebest 5kW wood burning stovesyou will likely be bewildered by the choice. There are many to choose from. The question I get asked most in our shop is “why should I pay <£1,000> for this one when this other one is just <£500>?”. Here is the very simple answer:the cheaper wood stoves are made in Chinaor Eastern Europe whilst the more expensive are made in Western Europe (or sometimes the USA). Here are a few examples where a more expensive stove might excel over a cheaper stove:

  • Aesthetics (more time spent on design)
  • Hinges (sometimes hidden on more expensive stoves)
  • Better quality glass
  • Thicker steel (longer life)
  • Improved door locking mechanisms
  • Longer warranty
  • Improved controllabilty of flame due to more resource invested on design of air flow within stove
  • Brushed steel fittings instead of cheapy chrome look

Open and close the door on a cheap Chinese stove. Then open and close the door on a DG stoveArada stovesWoodford stovesHamlet stoves or Saltfire stoves. You’ll understand the difference.

Stove pricing reminds me of wine pricing. A £20 bottle of wine is not double the quality of a £10 bottle of wine (the drinking experience might be improved by 20% as an example). We are talking “the law of diminishing returns here. They are all “fire in a metal box” at the end of the day.

Yes. However, there are specific regulations and restrictions in place to address air pollution concerns, particularly in areas designated as Smoke Control Areas. In these areas, only approved "smokeless" fuels or exempt appliances, such as Defra-approved wood-burning stoves, can be used. These stoves are designed to burn wood more efficiently and produce fewer emissions.

All the stoves we sell are DEFRA approved and Eco-design approved and suitable for all areas of the UK.

Terminology

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A stainless steel tube, slides down a brick/stone chimney to provide a smooth and safe route for smoke.

All of our stoves are approved by DEFRA to burn wood in all UK locations including Smoke Control Areas (towns and cities). Not all stoves are, so be careful if buying elsewhere.

All of our stoves are ECODESIGN approved to be sold in the UK. Not all stoves are, so be careful if buying elsewhere. ECODESIGN is mandatory by law since January 2022.

The base your stove sits on.

If the chimney is the polo mint then the flue is the hole.