You can extend a house in Peckham, but heritage rules cover more of the district than most buyers expect. Hundreds of buildings are listed. Fourteen conservation areas lie in and around it. The neighbours file planning applications at a rate that suggests everyone is trying anyway. Then there is the clay underneath, which moves with the weather and has its own opinion on foundations.
Historic England lists 322 buildings in and around Peckham. None is grade I, 2 are grade II* and the other 320 are grade II. Listing covers the inside of a building as well as the front, so on any of those 322 an extension, a new window or a removed wall needs listed building consent from Southwark Council, on top of planning permission where that applies. Peckham has no national monuments, just 320 buildings the council treats with very nearly the same care.
There are 14 conservation areas in and around the district, among them Holly Grove, Nunhead Green, Caroline Gardens, Cobourg Road, Glengall Road and Liverpool Grove. Inside them, changes that would go through without a second look elsewhere, to front elevations, roofs, windows and boundary walls, get the council's attention, and some need consent that an identical house outside the line would not. Holly Grove and Nunhead Green both sound like places that would mind about your windows. Both do. Southwark publishes its conservation-area boundaries, and the first thing to settle on any house is which side of one of those lines the front door is on.
None of this stops people trying. Southwark recorded 1,647 planning applications in Peckham between April 2024 and June 2026, and 688 of them were in the last twelve months. A district filing several applications a week is altering itself all the time and asking permission while it does it.
The ground deserves as much thought as the paperwork. The British Geological Survey rates Peckham at class 3 for shrink-swell, and all of the district reaches that class. Shrink-swell clay expands when wet and shrinks when dry, so an extension here generally needs deeper or more carefully designed foundations, and the structural engineer's view on the soil should come before the architect's view on the glass. Peckham's early suburbs dug the local London Clay for bricks, and an extension pays to dig that clay deeper.
Twelve listed buildings in and around Peckham are on Historic England's Heritage at Risk register. Those are buildings in poor condition, where a repair may attract grant money and will certainly attract scrutiny. They matter for whoever owns them. For someone buying an ordinary terrace on the next street, they mostly mean the conservation officer's time is already spoken for.
In practice the house decides. An unlisted home outside a conservation area can often take a modest rear extension under permitted development, the national rights that let some work go ahead without a planning application. A listed home, or one inside any of those 14 areas, should expect to apply, wait and discuss the brick.
Freedom to extend is one of Peckham's weaker points. It is possible, and plenty of people do it, but it is a negotiation with the council and the clay, and the house you choose decides how long that negotiation takes.