A red-brick mansion block with bay windows and wrought-iron balconies, converted into flats

SW1X · Belgravia · Westminster

Planning and building regulation drawings in Belgravia (SW1X)

Belgravia was laid out from the 1820s as a single set piece for the Grosvenor estate, and the streets still read that way: white-stucco terraces wrapped around garden squares, with cobbled mews tucked behind them. Eaton Square and Belgrave Square anchor the grandest of it, but the same discipline runs down through Lowndes Square, Wilton Crescent and Motcomb Street. Most of what's here is a hundred and eighty to two hundred years old, much of it statutorily listed, and almost all of it held on a long lease rather than freehold.

MCIAT chartered technologists
Westminster City Council granted 81% of 418 householder applications
Drawings in about 7 days

That combination changes what a project actually involves before a spade goes in the ground. Owners here are usually working through three layers at once: the council's planning process, listed-building consent where the property is listed, and the Grosvenor estate's own consent as freeholder. None of those three moves without the others, and skipping one tends to stall the whole thing later rather than earlier. A rear extension or a loft that would be uncontroversial elsewhere can turn into a longer conversation once rooflines, stucco detailing, railings and the uniformity of a terraced elevation are all part of what the conservation area is protecting.

Basements are their own subject. Westminster's basement policy sets out what depth and structural approach are acceptable and asks for an impact assessment before anything is dug, which shapes what's achievable below any of these garden-square properties. We map out which of these approvals a project needs, and in what order, before we start drawing, so the design that gets submitted is one the freeholder and the council can both say yes to.

Planning in Belgravia: what to know before you apply

Westminster treats a conservation area as the default here, not the exception, so a full planning application is the usual route even for modest changes, and listed-building consent often runs alongside it given how much of Belgravia carries listed status. The council's basement policy requires an impact assessment and caps scale and construction impact, which shapes anything below ground from the outset. On top of council sign-off, most leasehold work in Belgravia needs the Grosvenor estate's own consent as freeholder, a step that sits outside the planning system entirely but can hold up a project just as easily if it's left until last. We sequence these approvals so the drawings we submit answer all three at once rather than triggering a second round of consent later.

Applications are decided by Westminster City Council — its planning pages.

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Does your Belgravia project need planning permission?

Route check · Belgravia (SW1X)

ProjectProperty

Listed building?

Conservation area?

Likely permitted development — no planning applicationNeeds checking

A single-storey rear extension up to 4 m deep on a detached house, or 3 m on any other house, is Class A permitted development subject to the height and materials conditions.
An Article 4 direction applies here and may withdraw this freedom — the schedule must be checked before relying on it.
One or more constraints are unknown — we check the council's registers as part of the free appraisal.
Where permitted development applies, a lawful development certificate proves it for lenders and buyers.

Sources: GPDO 2015, Schedule 2, Part 1 · Planning Portal — common projects · Building Regulations 2010 — when approval is needed

This is a first-pass indication from the national rules, not planning advice for your property. Your council's registers, any Article 4 schedule and the exact dimensions decide it — the free appraisal checks all three before we recommend a route.

Confirm it with a free appraisal

Belgravia (SW1X) in numbers

What Westminster City Council has decided, and what SW1X is built of — the two facts that shape every job here.

Householder planning decisions — Westminster City Council

Belgravia (SW1X) applications are decided by Westminster City Council; these are its published householder figures for the last four quarters.

Householder applications decided2025 Q2 to 2026 Q1	418
Granted	340
Refused	78
Grantedof 418 decisions · England 90%	81%
Decided within 8 weeksof 230, excluding prior approvals	79%

Source: Ministry of Housing, Communities and Local Government (PS2 district planning application statistics). Open Government Licence v3.0 Extracted 2026-09-22.

Permitted development prior approvals — Westminster City Council

How the larger-home-extension route has fared with Westminster City Council, which decides SW1X notifications.

Larger home extension prior approvals — not required2024 Q2 to 2026 Q1	0
Prior approval granted	0
Prior approval refused	0

Source: Ministry of Housing, Communities and Local Government (PS1 district planning application statistics). Open Government Licence v3.0 Extracted 2026-09-22.

Planning appeals — Westminster City Council

Refusals in SW1X can be appealed to the Planning Inspectorate; this is Westminster City Council's householder appeal record.

Householder appeals determined2021–2026	124
Allowed	44
Allowedof 124 · England 36%	35%

Source: Planning Inspectorate appeals casework. Open Government Licence v3.0 Extracted 2026-09-22.

Conservation areas and Article 4 directions — Westminster City Council

Register counts for Westminster City Council. A count describes what the council has published, never a rank against another council.

Conservation areas in the register56 dated, 2008–2010	56
Article 4 directions in the register	10
Areas covered by an Article 4 direction	10

Source: MHCLG Planning Data Platform. Open Government Licence v3.0 Extracted 2026-09-22.

What SW1X is built of

Residential building form across Belgravia (SW1X), from 130 classified buildings — the fact that decides party walls, side returns and loft headroom before any policy does.

Attached on more than one side	96%
Attached on one side	4%
Detached	0%
Median building footprint	108 m²
Addresses per buildingAbove about 2 means flats and maisonettes dominate	2.79
Buildings classified	130

Source: Ordnance Survey National Geographic Database (derived statistics). Contains OS data © Crown copyright and database right 2026. Contains Royal Mail data © Royal Mail copyright and database right 2026. Extracted 2026-09-22.

Day 0Measured survey of your Belgravia property — or your existing plans if you have them.
About 7 daysDrawings issued for your approval. Free redraws until you are happy.
SubmissionWe validate against Westminster City Council’s checklist and submit on your behalf.
Council: 8-week targetHouseholder applications carry an 8-week statutory target. Westminster City Council decided 79% of 230 recent householder applications inside it.

Source: Ministry of Housing, Communities and Local Government (PS2 district planning application statistics). Open Government Licence v3.0 Extracted 2026-09-22.

Neighbourhoods

Streets and neighbourhoods in SW1X

Belgraviapredominantly early-to-mid nineteenth-century Grosvenor estate

Nearby

Nearby postcode districts

Pimlico SW1VBrixton Hill SW2Raynes Park SW20Chelsea SW3Wimbledon SW19Clapham SW4Earlsfield SW18Earl's Court SW5

FAQ

Belgravia (SW1X) — FAQs

Do I need listed-building consent for internal work in Belgravia, or just planning permission?+

It depends on the building, but a lot of Belgravia is statutorily listed, so internal reconfiguration, not just the façade, can trigger listed-building consent alongside a planning application. We check the listing entry for the specific address before assuming either way, because the two consents are assessed differently and missing one is a common cause of delay.

Does the Grosvenor estate need to approve my extension separately from the council?+

Usually, yes. Most properties in Belgravia are held on a long lease from the Grosvenor estate, and estate consent for external alterations is a separate step from planning permission and listed-building consent. We factor this in early so the design is drawn to satisfy the estate's requirements as well as Westminster's, rather than discovering a conflict after planning has already gone in.

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