Rear, side-return and wraparound extensions in South London

The single most valuable move most South London houses can make: a kitchen-dining space that opens to the garden, designed so the planning officer and the neighbours say yes.

Rear & side extensions by Alozie Architects

A well-designed extension does three things at once. It gives you the room your family has outgrown, it makes the whole ground floor work better rather than just adding a box, and it is approved without a fight. That third part is where most extensions go wrong, and it is what we are known for.

We start by checking what you can build under permitted development — many single-storey rear extensions up to 3 metres (attached houses) or 4 metres (detached) need no planning application at all, and the larger home extension route can take that to 6 or 8 metres with prior approval. If you are in a conservation area or want something outside those limits, we design for a householder application and pre-empt the officer's questions on daylight, the 45-degree rule and materials.

Every scheme comes with proper technical drawings and a Building Regulations package, so the builder you choose is pricing the same thing the council approved.

How it works

Every extensions project follows the same five stages — feasibility, concept, planning, technical design and on site — on a clear fixed-fee agreement covering design, planning and building regulations. Read about how we work.

Rear & side extensions: common questions

Do I need planning permission for a rear extension?
Often not. Single-storey rear extensions within permitted development limits — usually up to 3m deep on a terraced or semi-detached house and 4m on a detached house, under 4m high — can be built without an application, and the larger home extension scheme extends that to 6m/8m with a prior approval notification. Conservation areas, flats and listed buildings are different, so we check your property's status first.
What is a side-return extension?
On a Victorian or Edwardian terrace, the side return is the narrow strip of garden beside the rear projection. Infilling it turns a dark galley kitchen into a wide, light kitchen-diner. It is usually the highest-value extension a terrace can have.
How long does it take from first meeting to planning decision?
Typically 12 to 16 weeks: two to four weeks for survey and design, a week to prepare the application, and the council's 8-week statutory period. Pre-application advice adds a few weeks but can save months on a sensitive site.

Thinking about extensions? Tell us about the property.

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