House Extensions Chelsea

GS Renovation designs and builds extensions on Chelsea's period homes, from Georgian townhouses near the King's Road to Victorian properties across SW3. With over 30 years in the Royal Borough of Kensington and Chelsea, we handle foundations, steelwork, roofing and fit-out, and guide you through whether your project is permitted development or needs full planning permission.

Rear and side-return extensions in Chelsea

The most common extension across Chelsea's period stock is a rear or side-return addition that widens a cramped kitchen at the back of the house. We dig and pour new foundations, taking care around the mature trees and neighbouring structures typical of SW3 gardens, then build up in brick or with large glazed openings. Steel beams sized by a structural engineer carry the new openings and any removed rear wall, all inspected under the Building Regulations.

On larger plots we build double-storey and wrap-around extensions that add bedrooms and bathrooms above the new ground floor space. Whether your extension is permitted development or needs a full planning application depends on the property, and in Chelsea that balance tips towards planning because so much of the area is conservation-designated or listed. We assess your home, prepare the drawings and submit to the Royal Borough of Kensington and Chelsea where consent is required.

Planning and party walls in Chelsea

Chelsea sits almost entirely within conservation areas overseen by the Royal Borough of Kensington and Chelsea, and many townhouses are individually listed. That means extensions here rarely qualify as permitted development and usually need planning permission, with listed building consent on top where the property is protected. We advise honestly on what is achievable, design sympathetically to the Georgian and Regency character, and manage the application so your project starts on solid legal footing.

Because these houses are terraced, extensions almost always trigger the Party Wall etc. Act 1996, with excavation near the boundary and building against shared walls. You serve the correct notices and work with party wall surveyors before breaking ground. Once the shell is complete, our team handles the full fit-out, including plastering, electrics, plumbing, heating, flooring and decoration, so you deal with one contractor from foundations through to the finished, habitable room.

• Side-return and rear extensions
• Planning applications and permitted development assessments
• Flat and pitched roofs with rooflights or lanterns
• Bi-fold, sliding and French door openings to the garden
• Roof works and structural alterations at roof level

Work in Chelsea rarely sits on its own, so you may also want Open-plan conversion in Chelsea, House extensions across Kensington and Chelsea, side return infills and extension costs & planning.

Why Choose GS Renovation in Chelsea

Homeowners across SW3 choose GS Renovation because we manage the entire extension in-house, from planning drawings to groundworks, steel, roofing and finishing. With 30+ years in the Royal Borough of Kensington and Chelsea, we understand the conservation and listed constraints on period townhouses and deliver work that respects their character.

• Drainage diverted or built over with the right approval in place
• Party Wall notices served for excavation near a neighbour's wall
• Rated 4.9 from 31 reviews on MyBuilder
• Aftercare and snagging support once the job is finished
• Itemised pricing, so you can see what every stage costs
• Foundation depth set after trial holes, drains and trees are checked

Written and reviewed by Abdelaaziz Saaid, founder of GS Renovation Ltd, who has spent more than 30 years on the tools and on site in London homes. Structural design is specified by the consulting engineer appointed to your project.