House
extensions
in Victoria, SW1
Architects, Engineers, Surveyors & Builders Under One Roof.
One Studio. One Contract. One Team.
RICS surveying support for party walls, licence to alter, conservation-area works & neighbour mattersWe design and build Victoria house extensions across Ebury Street, Eccleston Street, Buckingham Palace Road - side-return, rear, wraparound and double-storey additions for Cubitt Stucco terraces, Grosvenor Estate townhouses and larger family homes where planning strategy, conservation detailing, Party Wall sequencing and structural engineering need handling properly.
House Extensions in Victoria: What You Need to Know
Every house extension project in Victoria is designed to respect the Belgravia Conservation Area and the character of Cubitt stucco terraces, Grosvenor Estate townhouses, mansion flats. Our in-house RIBA Chartered Architects handle Westminster planning applications, our chartered structural engineers specify any load-bearing work, and our directly-employed trades deliver the build under one fixed-price contract. We coordinate Building Control, Party Wall awards where needed, and all certifications through to handover.
In Victoria's conservation area, extensions must be designed with exceptional sensitivity. Westminster officers assess impact on the host building, neighbouring properties, and the wider streetscape. We secure planning approval through design excellence and thorough pre-application engagement.
Transitional area between Belgravia and Pimlico with mix of period and modern buildings. Victoria Street regeneration alongside traditional residential streets. Westminster planning. Our extensions in Victoria use materials and detailing that complement the existing architecture — whether matching traditional brickwork and stonework or introducing high-quality contemporary glazing and zinc cladding.
Victoria bridges Belgravia and Westminster, and an extension reflects that in-between character. The area lies in the City of Westminster, with conservation areas protecting its best stuccoed terraces around Ebury Street and Eccleston Street. Those streets carry handsome stuccoed terraces and Grosvenor Estate houses, restored with authentic stucco and joinery, while Buckingham Palace Road and Warwick Way add mansion flats and conversions — so the stock ranges from prime houses to leasehold blocks.
The estate and the commercial core both shape projects. Much of the finest stock is Grosvenor Estate townhouses, so an estate's requirements can sit alongside Westminster's decisions, and the area mixes prime residential streets with a busy commercial core that affects access and sequencing. Getting Westminster's conservation rules right early keeps a Victoria scheme on track, with any estate coordination built in from the start.
Cost tracks that layered ownership rather than plan area. A Victoria rear extension is generally £71,250 to £112,500 before VAT, a side return at £90,000 to £120,000, with a wraparound shown as an indicative £100,000 to £200,000 market band.
House Extensions in Victoria: Applied to the Local Stock
Victoria sits in the City of Westminster, on the streets between Belgravia and Westminster, with conservation areas protecting its best stuccoed terraces around Ebury Street and Eccleston Street. London-wide indicative market band for wraparound extension: £100,000–£200,000 (source VAT treatment unstated, shown as an indicative market band, not a normalised ex-VAT figure) (Resi wraparound extension guide, 2025).
Sources: Westminster City Council — Belgravia Conservation Area mini guide (May 2004) (2026); Wraparound extension (Resi wraparound extension guide, 2025) (2026)
What a House Extension Involves
An extension reshapes how the whole ground floor works, not just how big it is — the new structure, the opening into the existing house, the kitchen and the garden connection all have to be designed as one move. We take each project from feasibility drawings through consents, structure and fit-out under a single fixed-price contract. Most extensions we build include the scope below.
- Rear extensions — single-storey additions that open the back of the house to the garden
- Side-return & wraparound — infilling the side alley of a terrace, alone or combined with a rear addition
- Double-storey — new bedrooms or bathrooms above the ground-floor addition, designed to sit comfortably with the original roofline
- Foundations & steel — groundworks, beams and the opening into the existing house, engineered by our own structural team
- Glazing — rooflights, glazed roofs and slim-framed sliding or bi-fold doors specified for light and thermal performance
- Kitchen integration — the kitchen layout planned with the architecture from the first drawing, not squeezed in afterwards
- Services & heating — electrics, plumbing, drainage and underfloor heating built into the new floor
- External works — patio, drainage connections and garden reinstatement completed within the contract
How We Run Your Project
Six stages, with the consents and engineering settled before the first spade goes in.
- Feasibility visit — we assess the site, the boundaries and your brief, and identify the right consent route for your property.
- Design & approvals — our architects draw the scheme while planning or permitted development paperwork, structural calculations and party wall notices progress together.
- Fixed-price contract — every element specified and priced before construction, from foundations to door hardware.
- Groundworks & shell — excavation, foundations, walls, steel and roof, taken to weathertight while you carry on living in the house.
- Fit-out — insulation, services, glazing, kitchen, flooring and decoration, with the opening into the existing house formed once the shell is sealed.
- Completion — building control inspection, snagging, external works and handover with the full certification pack.
Read the full house extension guide for extension types, permitted development limits and the build programme stage by stage.
Many rear extensions can proceed under permitted development — broadly up to 3m deep on attached houses and 4m on detached, extendable to 6m and 8m through the prior approval scheme — but conservation areas, Article 4 directions and listed status change the picture, and every extension needs Building Regulations approval regardless of the planning route. Where foundations come within 3m of a neighbouring building, the Party Wall etc. Act 1996 obliges you to give adjoining owners a minimum of two months’ written notice before construction can begin. Our planning guide library sets out the rules for each borough.
Why Hampstead Renovations
We hold £10 million public liability insurance with Aviva; the certificate is available on request.
House Extensions in Victoria: Questions
How do Victoria's conservation areas affect an extension?
Victoria lies in the City of Westminster, along the streets between Belgravia and Westminster, with conservation areas protecting its best stuccoed terraces around Ebury Street and Eccleston Street. Those white-fronted period houses are restored with authentic stucco and joinery, so external change on a Victoria terrace is measured against that protected character.
Which Victoria streets have the grand houses for ambitious work?
Ebury Street and Eccleston Street carry handsome stuccoed terraces and Grosvenor Estate houses; Buckingham Palace Road and Warwick Way add mansion flats and conversions. Victoria bridges Belgravia and Westminster and mixes prime residential streets with a busy commercial core, so the grander terraces are the natural candidates for extension and reconfiguration.
What does an extension cost in Victoria?
London-wide guidance makes a Victoria rear extension generally £71,250 to £112,500 before VAT. A side return sits above that, at £90,000 to £120,000, with a wraparound at an indicative £100,000 to £200,000. Where a house sits on the Grosvenor Estate or has been divided into flats, the estate and leasehold coordination shape the figure alongside the works.
Does the Grosvenor Estate affect building work in Victoria?
It can. Much of the best stock is Grosvenor Estate townhouses, so an estate's requirements may apply alongside Westminster's decisions. Getting Westminster's conservation rules right early keeps a Victoria scheme on track, and where the estate is involved, that coordination is built into the programme from the outset.
What is the property stock like in Victoria?
Typical Victoria stock is stucco terraces, Grosvenor Estate townhouses and mansion flats. Its characteristic streets include Ebury Street, Eccleston Street, Buckingham Palace Road and Warwick Way, where prime residential runs sit beside a busy commercial core.
What is a side-return extension?
House Extensions in Nearby Areas
More Services in Victoria
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We survey your property, discuss your vision and provide a clear budget framework.