House Extensions in Mayfair, W1K
Rear, side-return, wraparound and double-storey extensions for houses in Mayfair, designed, approved and built by one team.
Covered under one contract
- Architectural and structural design
- Planning or lawful development certificate
- Foundations, walls, roof and steels
- Glazing, rooflights and doors
- Kitchen designed and fitted
- Building control and party wall handled
House Extensions in Mayfair.
An extension is the surest way to get the open-plan kitchen and dining room most families want, and the houses in Mayfair generally lend themselves to it: a side return to fill, a rear garden to build into, or on larger plots room for a full-width or double-storey addition.
We design the extension around how you will use it, not around the maximum footprint the rules allow. That means thinking about light, the level change to the garden, where the kitchen sits, how the old and new parts of the house meet and what happens to the rooms you already have. The structural engineering, party wall matters and building control inspections are all handled by us.
Approvals are checked on the first visit. Many single-storey rear extensions fall within permitted development, but the City of Westminster applies tighter rules in conservation areas and to flats and listed buildings, so we confirm the route before any drawings are produced and then manage the application if one is needed.
- Area
- Mayfair, W1K · W1J
- Council
- City of Westminster
- Housing
- Georgian townhouses, mews houses, Edwardian and inter-war mansion blocks, lateral apartments
- Transport
- Bond Street, Green Park
- Rear or side return, on site
- 10 to 16 weeks
- Design and approvals
- 8 to 14 weeks before start
- Glazing lead time
- 6 to 10 weeks, ordered early
- Consent
- Permitted development or householder application
- Party wall
- Notices served by us
Mayfair: the houses and the planning rules.
Mayfair is Georgian London at its grandest: the Grosvenor Estate's squares and streets, five-storey townhouses on Mount Street and South Audley Street, mews behind, and later mansion blocks and apartment buildings. Most houses are Grade II listed, the whole district is a conservation area, and the Grosvenor Estate exercises its own control over many properties.
We have fitted kitchens on South Audley Street, working with ebony veneers, Corian and Miele appliances in rooms with original cornices and shutters. Projects here are logistically demanding: restricted parking, timed deliveries, concierge buildings and neighbours who expect a quiet, tidy site.
The Mayfair Conservation Area covers the whole district.
Westminster City Council
Planning and listed building consent are decided by Westminster, with Historic England consulted on the most significant houses.
Grosvenor Estate
Where the freehold is held by the Grosvenor Estate, its own consent and design guidance apply in addition to the council's.
Basements
Westminster's basement policy limits depth and extent under gardens and requires a Basement Impact Assessment.
Approvals for house extensions in Mayfair.
Many single-storey rear extensions are permitted development within the 3 or 4 metre limits, or 6 and 8 metres under prior approval. Conservation areas, flats, listed buildings and larger schemes need a householder application, and every extension needs building regulations approval.
Planning and listed building consent are decided by Westminster, with Historic England consulted on the most significant houses.
What house extensions in Mayfair includes.
- Architectural and structural design
- Planning or lawful development certificate
- Foundations, walls, roof and steels
- Glazing, rooflights and doors
- Kitchen designed and fitted
- Building control and party wall handled
From site visit to handover.
- 01
Site visit & consultation
We visit, listen and measure. Brief, budget and constraints understood before any advice is given.
- 02
Design & itemised quote
Our architects and engineers draw the scheme, and from that we provide a transparent, itemised quotation for your approval.
- 03
Planning & approvals
Planning applications, building control and party wall matters handled for you.
- 04
Build, managed weekly
Our own trades, sequenced by a site manager. Progress reported every week.
- 05
Handover & aftercare
Joint snagging walk-through, documentation, and a guarantee on our workmanship.
House Extensions in Mayfair: your questions.
Do I need planning permission for an extension in Mayfair?
Not always. Permitted development covers many single-storey rear extensions on houses, but the City of Westminster removes those rights in some conservation areas, and flats and listed buildings always need an application. We confirm the route at the site visit.
How long does an extension take to build?
Ten to sixteen weeks on site for a single-storey extension once approvals are in place, plus the design and approval period beforehand. Glazing has the longest lead time, so we order it early.
Which parts of Mayfair do you cover?
All of Mayfair and W1K · W1J, including South Audley Street, Mount Street, Grosvenor Square, Curzon Street, Hill Street, Park Lane, and the neighbouring districts. We are based in London and our teams work across central, north, north-west, west and south-west London.
Our work near Mayfair.
Other services in Mayfair.
House Refurbishment in Mayfair
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Flat Refurbishment in Mayfair
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Structural Alterations in Mayfair
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Loft Conversions in Mayfair
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Basement Conversions in Mayfair
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Kitchen Renovation in Mayfair
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Bathroom Renovation in Mayfair
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Bespoke Joinery & Fitted Furniture in Mayfair
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Architectural & Interior Design in Mayfair
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Planning Permission & Building Regulations in Mayfair
Read moreHouse Extensions across London.
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We will visit, listen and explain what is possible for your property and how it would be approved. No pressure, no sales pitch.