GS Renovation builds house extensions across Mayfair and the wider W1 district, adding space to Georgian and Regency townhouses close to Hyde Park and the West End. With more than 30 years of experience, we handle groundworks, steel, roofing and fit-out, and guide you through Westminster City Council's planning and conservation requirements.
Rear and side-return extensions in Mayfair
Plots in Mayfair are generally tight and hemmed in by neighbouring townhouses, so extensions here tend to be modest rear or side-return additions, lower-ground enlargements or roof-level works rather than sprawling ground-floor builds. We assess the foundations, dig and underpin where the party wall and existing structure demand it, and tie new steel into the original brickwork so the extension carries its loads correctly and safely.
Because much of Mayfair is listed or falls within a Westminster conservation area, permitted development rights are usually restricted or removed altogether. That means most extensions here need a full planning application to the council, and often listed building consent as well, rather than proceeding under permitted development. We advise honestly on which route your property qualifies for before any drawings are commissioned, so there are no surprises later in the process.
Extending period townhouses across Mayfair
A typical Mayfair extension project runs from foundations and drainage through steel beams, roofing and a complete internal fit-out, all managed by one team. We match new brick and stone to the period elevation, replicate cornices and joinery inside, and detail the roof to suit the building's proportions. Where a rear wall is shared with an adjoining home, the Party Wall Act applies and you serve notices before any excavation begins.
Working in W1 means coordinating deliveries and skips on busy Westminster streets near Oxford Street and the West End, so we plan logistics tightly to keep disruption to your neighbours low. From the first structural survey to the final coat of paint, we sequence the trades so your extended kitchen-diner or additional bedroom is delivered as a single, accountable contract rather than a string of separate jobs.
- Steel goalpost frames where the rear wall opens up
- Building control inspections at foundation, damp course and steel stages
- Planning applications and permitted development assessments
- Side-return and rear extensions
- First fix and second fix plumbing and electrics throughout
Why Mayfair Homeowners Choose GS Renovation
Mayfair extensions are constrained by tight plots, listed status and strict Westminster planning, so experience matters. GS Renovation manages the planning route, structural steel and full fit-out under one roof, matching new work to the period fabric. With 30+ years across W1, we deliver additional space that respects the character of your home and the conservation area around it.
- Aftercare and snagging support once the job is finished
- Honest updates if a date or a detail has to move
- Neighbours given notice before the noisy stages
- Foundation depth set after trial holes, drains and trees are checked
- Garden levels and access made good where the build meets outside
- Waste cleared as we go, not left piled in the garden