Can you install a wood burner without a chimney?

Plenty of homes, from new builds to extensions and bungalows, were never built with a chimney. The good news is that a wood burner can still be an option. What you cannot do is run a wood-burning stove without any flue at all. The smoke and gases have to be carried safely outside, and that is the job a chimney normally does.

In short

• Yes, you can install a wood burner without a chimney by fitting a twin-wall insulated flue system, which acts as a factory-made chimney.
• The flue can run up inside the house, through ceilings and the roof, or outside, through a wall and up the exterior.
• It must meet Building Regulations (Approved Document J) for height, clearances and termination, and an external flue may need planning permission in some locations.

What is a twin-wall flue?

A twin-wall flue is two stainless steel pipes, one inside the other, with insulation packed between them. The insulation keeps the flue gases hot, which helps the stove draw properly, and keeps the outer skin cooler so it can pass safely near building materials when the correct clearances are kept. It is sold as a complete system with brackets, firestops, roof flashings and a terminal. Our guide to how twin-wall flues work goes into more detail.

Internal or external route?

Internal flue

The flue rises from the top of the stove, passes through the ceiling, any room or loft above, and out through the roof. Benefits include:

• The flue stays warmer, which usually helps the draw.
• Some heat is given off into the rooms it passes through.
• There is less visible pipework on the outside of the house.

The trade-off is that it takes up space in upstairs rooms or cupboards, and every floor and roof it passes through needs a proper firestop and weatherproof flashing. Where it runs through a bedroom or cupboard, it may need boxing in with suitable clearances.

External flue

The flue leaves the stove, goes straight out through the wall behind it, then climbs the outside of the building to above the roofline. This is often simpler inside the home and avoids disturbing upstairs rooms. However:

• It is more visible, which matters for planning in some areas.
• More of it is exposed to the cold, so the design needs to make sure it still draws well.
• Rear-exit stoves, or a stove with a short rear connection, are usually needed.

Flue height and position rules

Approved Document J sets out where a flue must terminate. A few of the key points:

• The flue for a solid fuel stove should usually be at least 4.5 metres tall, measured from the stove.
• If the outlet is at or within 600mm of the ridge, it should finish at least 600mm above the ridge. Further down the roof slope, other distance and height rules apply.
• The outlet must keep clear of openable windows, rooflights and neighbouring buildings.

Bungalows and single-storey extensions sometimes need a surprisingly tall flue to satisfy these rules, which is something a survey will pick up early.

Do you need planning permission?

For many houses in England, a flue is permitted development if it is on the rear or side elevation and rises no more than one metre above the highest part of the roof. However, in conservation areas and National Parks, an external flue should not go on a principal or side elevation facing a road, and listed buildings may need listed building consent. The safest approach is to check with your local planning authority before you commit.

Other things a no-chimney install involves

Hearth

The stove still needs a non-combustible hearth of the right size and thickness. In a room without a fireplace, this is usually a new hearth plate or a built-up constructional hearth, depending on the stove's tested hearth temperature. See our page on hearth preparation.

Ventilation

New homes are often very airtight, and stoves need air to burn safely. Depending on the stove output and how airtight the house is, a permanent vent or a stove with a direct external air supply may be needed.

Carbon monoxide alarm

In England, a carbon monoxide alarm is required in the room when a new fixed combustion appliance such as a wood burner is installed. Our guide on CO alarm requirements explains more.

Certification

The installation is notifiable building work. It is either self-certified by an installer registered with a competent person scheme such as HETAS, or Building Control must be notified before work starts.

How much more does it cost?

A twin-wall system is usually more expensive than lining an existing chimney, because of the length of insulated pipe, fittings and any roof work. As a very rough guide, published UK figures put the flue element at around £1,500 to £3,000 or more, but routes vary hugely. Our stove installation cost guide breaks this down further. These are indicative only, and a written quote is the only reliable figure.

Are there alternatives?

If a flue is not practical, some people choose an electric stove-effect fire or a gas stove with a balanced flue. These give a similar look without solid fuel, but they are a different product with different running costs, and they will not deliver a real wood fire.

Next steps

Whether an internal or external flue suits your home depends on the layout, roof, location and the stove you want. A site survey will confirm the best route, the flue height needed and any planning checks. If you would like to explore a twin-wall flue installation, get in touch to arrange a survey and a written quote.