The boiler goes on the first properly cold morning, and the instinct is to ring the nearest heating engineer. My advice for a listed house is to make one other call first, to your council, because a boiler swap that stays inside the footprint of the old one is a very different job from one that needs a new flue or new pipe routes.
New to this? Start with Our approach: one practice, from first idea to finished building
This is the heating question I am asked most as the nights draw in, and it follows on from what I would do about draughty windows. Keeping warm in an old house is partly about the boiler, and partly about what you ask the boiler to do to the building.
Four questions, in the order I would ask them
I would not start with the make of boiler. I would start here.
1. Is the new boiler going where the old one stood? A like-for-like swap, in the same place and on the same pipes, is the simplest case. I would still describe it to the council in a short email before the engineer books a date.
2. Where does the flue come out? A flue is the pipe that carries exhaust gas outside. A new one means a hole through a wall or roof, which is a permanent change to old fabric. The Planning Portal says that for a listed building "it is advisable to check with your local planning authority before a flue is fitted", and that flues "cannot exceed the highest part of the roof by one metre or more".
3. Which way do the new pipes run? Pipes are where old houses are most easily hurt. Floorboards come up, joists get notched, plaster is cut for a neat run. Bath and North East Somerset Council advises that "plumbing routes should avoid notching floor joists and should be installed parallel to them".
4. What happens to the radiators? The same council notes that modern radiators "have been developed which have high thermal efficiency", and that thermostatic valves can lower the temperature in unused rooms. A radiator is easy to move; an old plaster ceiling is not.
A flue is a hole in a wall that will outlive the boiler.
What the official sources say
I opened four pages for this piece, and I will keep to what they say.
The Planning Portal's boilers page says planning permission is "not normally required for the installation or replacement of a boiler or heating system if all the work is internal". That is about planning permission, which is a different thing from listed building consent. The same page tells anyone who lives in a listed building to "check with your local planning authority".
Section 7 of the 1990 Act says that no one may carry out works "for the demolition of a listed building or for its alteration or extension in any manner which would affect its character as a building of special architectural or historic interest" unless they are authorised (section 7 of the 1990 Act). Whether a particular flue or pipe route "affects its character" is a judgement for your council, on your building.
One council gives its answer plainly. Bath and North East Somerset says listed building consent "is required for a new boiler installation where it will involve and extract vent", and the page treats new service runs, which are the pipes, as something that can affect historic fabric. That is one council's published position, not a national rule, and yours may differ. Ask yours.
GOV.UK's planning practice guidance says that where there is doubt, it encourages owners "to discuss the matter with the local planning authority", and to do so before submitting any application.
Where the flue could go
Bath and North East Somerset's advice, which I think is sound as a starting point, is that "principal elevations should be avoided for extract flues", that the outlet should be discreet, and that, where practical, the exhaust should go through "a vertical flue in a roof that cannot be seen". It adds that flues have to be located so that they comply with the Building Regulations, so the best place for the building is not always the place the engineer's regulations allow.
My own method, which is judgement and not a rule: I walk round the outside first and decide which wall the council would least mind. Only then do I talk to the heating engineer about where a flue can physically run.
Before the engineer comes
| Do now | Leave until you have spoken to the council |
|---|---|
| Note the boiler's make, age and position, and photograph the room | Cutting any new hole through an outside wall or roof |
| Photograph the existing pipe runs, outside and under floors | Lifting historic floorboards or cutting plaster for new pipes |
| Draw the proposed flue and pipe routes on a sketch plan | Moving or removing historic radiators, grates or chimney breasts |
| Check whether the house is also in a conservation area | Ordering equipment that fits only one position |
Photographs matter more than owners expect, because they show what the building looked like before, and they make a short conversation with a council officer far easier.
If a failed boiler leaves you cold, a temporary electric heater or two buys the time to ask properly. Nothing in this advice is a reason to sit in a freezing house for weeks, and I would raise it with the council on day one so that nobody is surprised.
A calmer way to go about it
I am wary of urgency in this work. The cold makes people hurry, and hurried heating jobs are the ones that leave a scar in a wall. A short, early conversation, and one clear sketch, usually save the owner more time than they take.
The other thing I would say is that the heating is part of the house's story, not a bolt-on. The way a house is warmed is also what allows its fires and its rooms to be used as they were meant to be. My approach is to start from the building and work out towards the equipment, and the questions and answers page covers the first steps if you are new to listed building work.
Speak to Giles if a boiler has failed and you want to think it through first: book a conversation, get in touch, call +44 (0)7737 745211, or send a WhatsApp voice note.
Giles Paul Shorter — ARB registered · RIBA Chartered Member · on the RIBA Conservation Register · 17+ years specialising in listed and historic buildings.
- Planning (Listed Buildings and Conservation Areas) Act 1990, section 7 — Restriction on works affecting listed buildings ↗ (accessed 2026-11-09)
- GOV.UK — Planning practice guidance: Conserving and enhancing the historic environment ↗ (accessed 2026-11-09)
- Planning Portal — Boilers and heating ↗ (accessed 2026-11-09)
- Bath & North East Somerset Council — Sustainable construction and retrofitting: boiler and heating ↗ (accessed 2026-11-09)
Text © 2026 SOANE Architects Ltd. You’re welcome to quote a short extract with a credit and a link back. Photographs belong to their photographers and are credited beneath each image.