Side Return Extensions
Reclaim your side return. Transform your ground floor.
Side return extensions for Victorian and Edwardian terraces across London. Open up narrow kitchens, create open-plan living spaces and maximise every square metre of your property.
Specialist side return extension contractors in London.
The side return — that narrow strip running alongside your kitchen — is one of the most underused spaces in London terrace houses. A well-designed side return extension transforms a cramped galley kitchen into a bright, open-plan living and dining area.
RCB specialises in side return extensions across London, particularly on Victorian and Edwardian terraced properties. We handle planning assessments, structural engineering, party wall coordination and the full build — from foundations through to handover.
Whether you want a simple infill to widen your kitchen or a full side return and rear extension to completely reimagine your ground floor, RCB delivers it with the structural integrity and finish quality your home deserves.
What's included
A side return extension can add 10-15% to your property value and transform your ground floor layout
How It Works
The RCB process for this service.
Site Assessment
We survey your property, measure the side return, assess planning options and identify any structural or party wall considerations.
Design & Approvals
Architectural drawings, planning application or Permitted Development confirmation, structural calculations and Building Regulations submission.
Detailed Estimate
A fully itemised estimate covering every element — foundations, steel, roof, envelope, internals and finishes. No hidden costs.
Build & Handover
RCB manages the full build — groundworks, structure, roof, internal fit-out, decoration and Building Control completion certificate.
Planning & Regulations
Most side return extensions on terraced properties fall within Permitted Development rights, subject to size limits and conditions. However, properties in conservation areas or with Article 4 directions may require a full planning application. Party wall notices are almost always required as the side return typically borders a neighbour. Building Regulations approval is mandatory. RCB coordinates all of this for you.
FAQs
Common questions.
Do I need planning permission for a side return extension?
In many cases, a side return extension falls within Permitted Development rights and does not require a planning application — provided it meets size and height conditions. However, if your property is in a conservation area, is a listed building, or has an Article 4 direction in place, you will likely need full planning permission. RCB will assess your specific situation at the outset.
How much does a side return extension cost in London?
Side return extensions in London typically start from £35,000 for a straightforward infill and can reach £60,000–£80,000 for larger side-and-rear combinations with high-specification finishes. Costs depend on size, structural requirements, roof design (flat, glazed, pitched) and internal specification. RCB provides a fully itemised estimate once the scope is defined.
Will I need a party wall agreement?
Almost certainly yes. Side return extensions are built adjacent to or very close to the boundary with your neighbour. A Party Wall Notice must be served before work begins. If your neighbour does not consent, a Party Wall Award will need to be agreed. RCB will advise you on the process and timelines.
Can I have a glass roof on my side return extension?
Yes — glass or glazed roofs are very popular on side return extensions as they flood the space with natural light. Options include structural glass panels, rooflights, or a combination of flat roof with large skylights. RCB can advise on the best approach for your property and budget.
How long does a side return extension take to build?
A typical side return extension takes 8–14 weeks on site from groundworks to completion, depending on the size and complexity. Pre-construction — design, planning, structural engineering and party wall — typically adds 8–16 weeks. RCB will provide a realistic programme at the estimate stage.
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