Can you have a wood burning stove with no chimney?

What a twin-wall flue is

Twin-wall is insulated flue pipe made for homes without a masonry chimney. It has two skins of stainless steel with insulation between them, which keeps the gases warm so they rise and draw cleanly, while the outside stays cool enough to pass safely through floors, ceilings and walls.

Internal or external route

An internal route runs up inside the house, through the ceilings and out through the roof. It keeps the flue warm, which helps the draw, and it can be boxed in neatly. An external route goes out through the wall behind the stove and up the outside of the house above the roofline, which keeps the work out of your rooms.

Which is better depends on the layout of your home, and we work out the best route on the survey.

What it involves

Every twin-wall system is designed for the property, taking in the construction of the house, the position of the stove, the room layout and the height of the building. We specify all the components, from the firestops and brackets to the cowl at the top, so the finished system is safe, compliant and performs well for years.

Where the flue can and cannot go

A twin-wall system has rules, and they are sensible ones: minimum distances from windows, doors and eaves, a terminal high enough above the roofline to draw cleanly, and safe clearances where the flue passes through floors, ceilings or walls. Building Regulations set the specifics, and we design every route to them, which is why the survey walks the whole path from stove to sky before anything is quoted.

In practice most homes offer two workable routes, internal or external, and the choice comes down to the room layout, the roof and how visible you want the flue to be. Some of our best installations make a feature of it: a freestanding stove with a clean black flue rising through a double-height space is architecture, not plumbing.

Do you need planning permission for an external flue?

Usually not: most domestic flues fall under permitted development. The exceptions are the ones you would guess: listed buildings, conservation areas and National Park settings where a visible external flue changes the look of the building. In those cases we plan the route sympathetically and tell you plainly if anything is worth checking with the council before work starts.

Internal routes through the roof often sidestep the question entirely, which is one of several reasons we frequently prefer them.

What a twin-wall installation costs and why

Twin-wall systems start from around £3,500 because there is simply more of everything: insulated flue components, structural supports, firestop plates at every floor level, weathering at the roof and the terminal on top. Every part is specified for your building, which is engineering rather than shopping.

Set against that, you are not paying for chimney repairs, lining or sweeping an old flue back to health, and the system is designed around your stove from day one. For the garden rooms, barns and modern homes we fit them in, it is the right money in the right place.

Common questions