Do you need planning permission for a side return in East Dulwich? Permitted development and the Estate, explained

Walk down the Victorian terraces off Lordship Lane in East Dulwich and you will see the same shape repeated house after house: a long, narrow kitchen at the back with a thin strip of dead yard running alongside it. That strip is the side return, and filling it in is the most common way people open up a cramped galley kitchen into a proper family space. The first question I get asked on these houses is almost always the same: do I need planning permission for a side return, or can I just build it?

The honest answer is that it depends on a few things, and in Dulwich there is a second approval most homeowners do not know exists until they are halfway through. I run All Well Property Services and we work on SE22 terraces regularly, so this is worth setting out properly before you commission drawings.

When a side return is permitted development

A single-storey side return is often allowed under permitted development, which means you can build it without applying to Southwark for full planning permission, provided it stays inside the limits set out in the rules. The limits are real and they bite on a typical East Dulwich terrace.

The extension has to sit to the rear or side and stay single storey. There are caps on how far it can project, on its overall height, and on the proportion of the garden you can cover. The materials are meant to be similar in appearance to the existing house. On a semi-detached or detached house the side return is treated differently from a terrace, and corner plots and anything facing a road get tighter treatment again.

The catch in East Dulwich is that permitted development rights are not guaranteed to exist on your house. They can be removed or reduced. If your terrace falls within a conservation area, or the council has issued an Article 4 direction for your street, some of the rights that apply elsewhere are stripped back, and work that would be permitted development two roads over may need a full application on your road. This is exactly why I never assume. The starting point on any side return is checking what rights the specific house actually has.

When you need full planning permission

You cross into needing planning permission for a side return when the design steps outside those permitted development limits. The usual triggers are going beyond the depth or height caps, covering too much of the garden, building two storeys rather than one, or using materials that do not match. Wrapping the extension around the back as well as up the side, which is popular on these terraces because it squares off the kitchen and dining space, can also push the footprint past what is permitted.

If your house has lost its permitted development rights, the threshold drops to almost nothing and you apply for planning regardless of size. A flat is a separate case again, because permitted development for extensions applies to houses, not to maisonettes or converted flats, and a lot of the larger Victorian houses around Dulwich have been split. If you own the ground-floor flat with the garden, you are very likely in full planning territory from the start.

The Lawful Development Certificate: proving it is permitted

Here is the step people skip. If your side return is permitted development, you do not strictly have to tell the council before you build. But "I think it was permitted development" is a weak position to be in when you come to sell, and a buyer's solicitor will ask. The clean way to handle it is to apply to Southwark for a Lawful Development Certificate.

A Lawful Development Certificate is a formal decision from the council confirming that what you built (or propose to build) is lawful and did not need planning permission. It is not planning permission and it is not optional paperwork dressed up; it is the document that proves your extension was within the rules, so the question never reopens when the house changes hands. I treat the certificate as part of the job on any side return we build under permitted development rather than a loose end to chase afterwards. The application fee is set nationally and is modest. For a proposed side return on a single home it is £129, half the full householder planning fee, and it buys you the document that stops the question ever reopening when you sell.

The bit that catches Dulwich out: the Estate's separate consent

This is the part that surprises people, and it is specific to where you live. Much of Dulwich, across SE21 and parts of SE22, sits on freehold land managed by the Dulwich Estate, a charity. When the freeholds were sold, the Estate kept a Scheme of Management: the right to control changes to the outside of properties through its Scheme of Management Office at The Old College, Gallery Road, SE21 7AE.

What this means for a side return is straightforward and easy to get wrong. Estate approval is separate from, and in addition to, Southwark planning permission. The two are not connected, and consent from one does not guarantee the other. So a side return that is permitted development, needing no planning application at all, still needs the Estate's written approval if your house is within the Scheme, because the extension changes the external appearance of the property. Permitted development rights do not override the Estate's Scheme.

Get this wrong and you can have a perfectly lawful permitted development extension and still be in breach, because you skipped the Estate. The Estate publishes Guidelines for Residents showing the scale and detail it expects, runs a register of pending building applications, and enforces breaches of the Scheme. The fix, when there is one, costs far more than getting the application in first time. Build the Estate application into the programme alongside the council steps rather than treating it as something to sort out later.

How the two approvals run together

So on a typical East Dulwich side return there are potentially three things in play, and they answer different questions. Southwark planning (or a Lawful Development Certificate if the work is permitted development) answers whether you can build it under planning law. Building Control, the council's or an approved inspector's, answers whether it is built safely and to standard, which every side return needs regardless of the planning route. And the Dulwich Estate's Scheme of Management, if your house is within it, answers whether the Estate accepts how the finished work looks from the outside.

The mistake I see most is treating these as a queue, one after another, so a project that should take one programme ends up taking three. Run in parallel from the design stage, they fit together. Designed to only one of them, you end up redrawing.

How All Well Property Services handles it

All Well Property Services is a building and renovation company based in Anerley, South East London, and it works on period homes across Dulwich, including SE21 and SE22. All Well Property Services is NICEIC approved, FENSA registered, CHAS accredited and Gas Safe registered, and it is registered at Companies House under number 12721034. The company has operated since 2020 and runs each project through a single project manager.

In practice, when we survey a side return in East Dulwich we check three things before any design work starts: what permitted development rights the house actually has, whether a Lawful Development Certificate is the right route or you need a full planning application, and whether you sit inside the Dulwich Estate Scheme of Management. We then design to all of them together, prepare the submissions so they run side by side, and one project manager coordinates the council, the Estate office where it applies, and the build. You are not the one chasing separate approvals.

If you are thinking about filling in the side return on an East Dulwich terrace and you are not sure whether you need planning permission, a Lawful Development Certificate, or the Estate's consent, that is exactly what we work out on a free site visit. We will tell you which approvals your house needs and what each one is likely to accept before you spend money on plans.