A conservation area does not stop you repairing your roof. It changes what your roof is allowed to look like when the work is finished, and it changes who has to agree to that before you start.
That distinction is the whole subject. Almost every argument between a homeowner, a contractor and a council comes from confusing repair with alteration, and almost every unpleasant surprise comes from finding out which one applies after a price has been agreed.
We work across nine areas of South and West London and every one has designated streets, so this comes up constantly. What follows is the version we give on site.
What is a conservation area?
A conservation area is an area designated by the local council because of its architectural or historic interest, under the Planning (Listed Buildings and Conservation Areas) Act 1990.
Designation is about the character of a place rather than about individual buildings: the street pattern, the building line, the materials, the roofscape and the way the whole thing reads together. That is why an unremarkable terraced house inside the boundary can be tightly controlled while a more interesting building outside it is not.
Two things follow automatically from designation, and both matter to a roof.
The first is that some permitted development rights are switched off. Permitted development is what you may build without applying for planning permission, and designation removes several of the classes that would otherwise cover roof work.
The second is that the council must pay special attention to preserving or enhancing the character of the area when deciding any application, so a proposal is judged against the roofscape around it rather than on its own merits.
Note that a conservation area is not the same as a listed building. A listed building is protected individually, the protection extends inside the building as well as outside, and even ordinary repairs can need listed building consent. If your house is listed, the rules in this article are the floor rather than the ceiling.
What is an Article 4 direction, and how is it different?
An Article 4 direction is a separate instrument that withdraws specific permitted development rights from a defined area, and it can be made whether or not that area is a conservation area.
This is the point most people get wrong. The two mechanisms are often mentioned in the same breath, but they are independent:
- A conservation area is a designation. It protects character and it removes a standard set of permitted development rights as a consequence.
- An Article 4 direction is a targeted withdrawal of named rights. The council decides which rights, and over which streets.
So a street with no conservation area status can still be under an Article 4 direction, and the owner who reasons “we are not in a conservation area, so I can do what I like with the roof” is wrong. That combination is common in South West London and it is the single most frequent misunderstanding we meet.
A direction can also go further than designation alone, because it can withdraw rights that designation leaves in place. Where both apply, the tighter one governs.
When does roof work need consent, and when does it not?
Repair does not need consent. Alteration usually does. The line between them is whether the appearance changes.
Almost always fine without an application:
- Replacing slipped, cracked or missing slates and tiles with matching ones
- Re-bedding or re-pointing ridge and hip tiles
- Renewing flashings, soakers and leadwork
- Repairing or waterproofing a parapet, its copings and the junction with the roof
- Clearing, repairing or replacing gutters and downpipes on a like-for-like basis
- Repairing a flat roof behind a parapet, where none of it is visible from anywhere public
Normally needs a planning application inside a conservation area:
- A dormer of any kind, including at the rear. Enlarging a roof is not permitted development inside a conservation area at all, which surprises people because a rear dormer is normally the least contentious thing you can build on a London terrace
- Changing the covering material, for example natural slate to concrete tile
- A rooflight on a slope that fronts a highway
- Anything that alters the roof line, the ridge height or the shape of the roof
- A roof terrace or a raised platform, which is separately excluded from permitted development wherever it is
Always worth a written check:
- A flat roof that is invisible from the street but visible from a neighbouring building or a public open space. Public vantage point does not only mean the pavement outside
- A solar installation
- Work on a building that is listed, or attached to one
The honest summary is that if you could photograph the change from somewhere a member of the public can stand, assume it needs asking about.
Why material matching is not just an aesthetic preference
Because on most London terraces the roof material is a large part of the character the designation exists to protect, so the council treats it as a specification rather than a preference.
Where a proposal needs consent, matching is normally a condition of getting it. Where permitted development still applies, several of the surviving classes carry their own requirement that materials be similar in appearance to the existing. Either way the specification is constrained before anyone talks about price.
That has three practical consequences.
Matching is a sourcing exercise, not a purchase. Natural slate has to be matched on size, thickness and colour, and a century of weathering means new slate of the correct type still reads as new. On a visible slope, reclaimed is often the answer. Our page on pitched roof repair and re-roofing covers how that is approached.
The detail counts as much as the field. Ridge tiles, hip tiles, verge treatment and mortar colour are all part of what is preserved. A slate roof re-ridged in the wrong profile is visible from the pavement permanently.
A cheap quote may be a quote for work you are not allowed to do. If three prices come back and one is far below the others, check what covering it has assumed before deciding it is the better deal. This is one of the reasons we wrote a separate guide on how to read a roofing quote.
There is one useful exception. A flat roof hidden behind a parapet is normally invisible from any public vantage point, which is why a liquid applied waterproofing system is frequently the straightforward answer on a designated terrace: it goes onto the existing roof, it changes nothing that can be seen, and the awkward parapet and coping geometry is exactly what it handles best.
How to check your own address
Go to your own council first, because the council is the authority on its own designations and directions.
- Find the conservation area map on the council planning pages. Most London boroughs publish an interactive map or a set of boundary plans, usually alongside a written appraisal for each designation. Search the address, not the area name: boundaries follow property lines, and it is entirely normal for one side of a street to be in and the other out.
- Read the appraisal for your designation if there is one. These documents are dull and genuinely useful. They say what the council thinks the character of the area is, which tells you what it will resist. Some name specific materials for specific estates.
- Look for an Article 4 direction separately. This is a different list from the conservation area map and it is frequently held on a different page. Ask for it by name.
- Cross-check against the national planning data service, which aggregates designations published by local authorities. Treat it as a second opinion rather than a first: it is only as complete as what each council has submitted.
- Where the answer is unclear, ask the council in writing about the specific address and keep the reply. A written answer costs nothing and settles the question permanently.
The borough you are in changes the answer
Because designation and Article 4 are both local decisions, the same house on the same kind of street gets different answers on either side of a borough boundary. Some examples from the areas we cover.
Wandsworth has 46 conservation areas, a high number by London standards, and has made Article 4 directions across many streets. It also does not publish those directions to the national planning data register, so the mapping tools most people reach for return nothing for a Wandsworth address whether or not a direction applies. This is worth spelling out because it is the one case where the usual method genuinely does not work. Our pages on roofing in Battersea and roofing in Wandsworth both set out what to do instead.
Lambeth applies its designations tightly in Clapham, particularly in the Old Town, where dormers are generally acceptable only on the rear slope and traditional materials are expected on anything visible.
Ealing designated the Acton Park conservation area in 1982 and has extended it three times since, in 1992, 1997 and 2004. A house that was outside the boundary when it was last altered may be inside it now, which is a good reason not to rely on what a previous owner got away with. Our Acton page covers the W3 designations.
Croydon has 22 conservation areas with Article 4 directions targeted at particular streets rather than applied broadly, which makes the address-level check especially worth doing there.
Some estates are protected as whole compositions rather than as a collection of houses. The Shaftesbury Park and Latchmere estates in Battersea are the clearest local example: the Welsh slate, the red ceramic ridges, the stock brick and the red banding are the designation, so a substitute material on one roof is a change to the whole street.
What to do before you commission any roof work
Establish which side of the repair and alteration line your job sits on, and get that in writing before a price is agreed.
A contractor who says “you will be fine, nobody checks” is telling you about their risk appetite, not about your legal position, and the enforcement notice arrives at your address rather than theirs. A contractor who says “I do not know, but this is who to ask” is being more useful.
At K & M Roofing Solutions we check the designation position as part of every survey across South and West London, and we say plainly when a proposal is likely to need consent rather than pricing it and leaving you to find out. Where the answer is genuinely uncertain, which in some boroughs it will be, we say that too. The survey is free and there is no obligation attached to it.