The short answer
It depends on the house. On a listed building, swapping cast iron for plastic is a change B&NES will want to see before work starts, and consent may be needed. In a conservation area the street matters, and so does what the gutters are now. Unlisted houses outside both are the simple case. Check with B&NES planning first, and expect cast iron or cast aluminium to be the safer match on a period front.
Three situations, three different answers
The question sounds simple, yet it covers three quite different houses. Which one you own decides how much checking you need to do.
A listed building has the strictest position. Listed building consent is a separate application from planning permission, and B&NES treats work done without it as a criminal matter. Guttering belongs to the face of a listed house as much as its windows do, so a change of material or profile needs a conversation with the council ahead of any scaffold. Ring the planning team first.
A house in a conservation area is not listed, but the area is protected because of its character. The city-wide conservation area takes in roughly half of the World Heritage Site, which means one Bath street can be inside it while the next is not. Some streets also have Article 4 directions that remove certain permitted development rights. B&NES keeps a policy map of those streets, and one phone call to planning will tell you where yours falls.
A period house outside both is the simplest case. There is no consent route to follow, although the usual good sense about matching the building still applies.
Why plastic looks wrong on an older front
Planning officers are not objecting to uPVC out of snobbery. You can see the difference from across the road. A cast iron gutter has a deep, rounded section, a crisp bead along the lip and joints that are bolted and sealed. A plastic gutter is thinner, its brackets are visible and its joint clips sit proud of the line. On a stone terrace with a parapet or a deep cornice, that thin profile can look like a pencil line where the building expects a moulding.
Colour is part of it too. The colour choice in plastic is narrow and it fades unevenly in sunlight, and a white fascia and gutter set against honey-coloured stone draws the eye to the roofline. Cast iron and aluminium are painted on site or at the factory, and a dark, matt finish recedes against the wall in the way the original did.
Behind the appearance there is a practical point as well. Plastic expands and contracts with temperature more than metal does, so long runs need expansion joints that are easy to see. Where the original gutter was built into the stonework or sat behind a parapet, a plastic replacement may not fit the space at all.
What the council looks at
When a householder or a roofer asks about replacing gutters on a protected building, the council is generally weighing the same few things. It wants to know the material, the profile, the colour and the way the gutter meets the wall or roofline. Photographs of the existing gutters and a simple description of the proposed ones go a long way.
Like-for-like repair is treated more gently than a change of material. Replacing a length of cast iron with the same pattern of cast iron keeps the building as it was. Replacing the whole run with plastic changes it. If you cannot tell whether your proposal counts as a repair or a change, ask. The B&NES conservation team can be reached through the council website, and the answer costs nothing.
Whether consent is needed is the council's decision and not ours. What we can do is explain what the council is likely to ask and photograph the existing gutters so that you have something to send. Our page on gutters on listed buildings goes into the consent side in more detail.
The fitting options that suit a period house
Cast iron is the traditional answer and still the correct choice on plenty of listed fronts. It is heavy, so it wants firm brackets and a fascia or wall that will hold the weight, and it needs painting every few years to stay in good order. Typical lifespans reported for cast iron run from 40 to 70 years, and sometimes more, though that comes from a single cleaning firm's guide and depends on how it is looked after. Our guide to cast iron guttering cost shows what drives the price.
Cast aluminium is made in profiles that copy the old cast iron sections, from the half-round to the ogee. It is lighter, does not rust and takes a factory-applied paint finish. To the eye from the street it reads as cast iron, which is why conservation officers are often more relaxed about it than about plastic. It is not a substitute for cast iron on every listed building, and the council still has the final say, but it is a sensible thing to propose.
Retaining and repairing what is there is often the lowest-cost option, and councils usually welcome it. A leaking joint can be rebuilt, a cracked length replaced, and the rest repainted and re-bracketed. That keeps the original material and the original line.
If the house is not protected and plastic suits the budget, it is a fair option. Typical UK guttering costs are about £30 to £70 per metre, according to MyBuilder's 2026 guide, Scaffold comes on top, and a written fixed price arrives once we have surveyed the house.
How we would approach your house
We start by looking at the gutters from the pavement first and then from a ladder or tower. We note the material, the profile, the bracket type and the state of the fascia behind. If the board is rotten, the gutter has nothing sound to fix to, whatever the material.
Then we ask the questions that decide the route: is the house listed, is it in the conservation area, and has anyone altered the gutters before? A house that already has plastic gutters from a previous owner is a different conversation from one with the original cast iron, since putting back the original pattern is generally welcomed.
From there we give you a written price with the survey photographs, and where consent is needed we make clear that the order should wait for it. On older roofs we match materials, so cast iron guttering stays metal wherever the building calls for it. Where an old cast iron length can be saved, we clean it back, treat the rust and refit it, so only the cracked sections need new castings.
For the wider picture on the roofline, including soffits and fascias, see our gutters, soffits and fascias service. Guards often get suggested with a new run, so our view on gutter guards is worth reading before you agree to them.
