L-shaped dormer loft in Westminster

Which Westminster postcodes does this l shaped dormer service cover?

Every Westminster postcode district we draw in, the stock that dominates it and the authority that validates a l shaped dormer there. Westminster fees below are the statutory England rates for 2026, not l shaped dormer estimates.

How does a l shaped dormer differ street by street across Westminster?

Roof pitch, wall build-up and plot depth change every few Westminster streets, and each one changes what a l shaped dormer can achieve at that address.

• Paddington (W2) — a l shaped dormer in Paddington starts from regency terraces, modern apartments, and Paddington reads as Regency and Victorian terraces, canal-side regen. Shallow modern roof pitches rarely leave the head height a dormer needs in W2. Westminster City Council assesses Paddington l shaped dormers against its own Paddington character guidance, and the location plan we draw for Paddington references Paddington Basin.
• Victoria (SW1E, SW1W) — a l shaped dormer in Victoria starts from regency terraces, post-war flats, and Victoria reads as Regency terraces, mixed-use. Trussed post-war roofs need a full structural redesign before a dormer in SW1E. Westminster City Council assesses Victoria l shaped dormers against its own Victoria character guidance, and the location plan we draw for Victoria references Victoria Station.
• Westbourne Green (W2, W9) — a l shaped dormer in Westbourne Green starts from victorian terraces, mansion blocks, and Westbourne Green reads as Victorian terraces and mansion blocks. Full-width rear dormers on Victorian terraces here are the default in W2. Westminster City Council assesses Westbourne Green l shaped dormers against its own Westbourne Green character guidance, and the location plan we draw for Westbourne Green references Royal Oak.
• Maida Vale (W9) — Edwardian mansion blocks, canal-side defines Maida Vale, where edwardian mansion blocks, victorian villas set what a l shaped dormer can do. Full-width rear dormers on Victorian terraces here are the default across W9. Any Maida Vale l shaped dormer is validated by Westminster City Council, with Little Venice the usual Maida Vale reference point on the site plan.
• Mayfair (W1J, W1K) — a l shaped dormer in Mayfair starts from georgian townhouses, listed buildings, and Mayfair reads as Georgian listed townhouses, luxury. A dormer on a Georgian roof has to sit behind the parapet line to stand any chance of consent in W1J. Westminster City Council assesses Mayfair l shaped dormers against its own Mayfair character guidance, and the location plan we draw for Mayfair references Berkeley Square.
• Belgravia (SW1X, SW1W) — white stucco Regency terraces defines Belgravia, where regency stucco terraces, listed buildings set what a l shaped dormer can do. Full-width rear dormers on Victorian terraces here are the default across SW1X. Any Belgravia l shaped dormer is validated by Westminster City Council, with Eaton Square the usual Belgravia reference point on the site plan.
• Marylebone (W1U, W1G, W1H) — l shaped dormer work in Marylebone means georgian terraces, edwardian mansion blocks. Marylebone is Georgian and Victorian terraces, mansion blocks. A dormer on a Georgian roof has to sit behind the parapet line to stand any chance of consent throughout W1U. Westminster City Council decides the Marylebone application, and Marylebone High Street anchors the Marylebone location plan.

Does Westminster planning policy restrict a l shaped dormer?

Conservation areas covering Westminster: Westminster City Council runs 56, and Pimlico, Soho, Covent Garden are the ones Westminster owners meet most. A l shaped dormer inside a Westminster conservation area loses permitted development, so the Westminster submission is a householder application at £548 decided in 8 weeks — not a £249 prior approval decided in 6 weeks. In St John's Wood a l shaped dormer is judged on the street elevation first.

Westminster and Article 4: Multiple Article 4 Directions — office-to-residential restrictions, HMO conversions, retail to residential in shopping zones. A l shaped dormer planned at a NW8 address is checked against that direction first; Westminster City Council publishes the Westminster extent, and the NW8 line rarely follows the Westminster boundary you would expect.

Westminster below-ground policy: Westminster basement policy restricts to single-storey, typically under 50% of rear garden footprint; lightwells and rooflights strictly controlled in conservation areas. Any l shaped dormer in Westminster that goes below existing foundations triggers two months notice under section 6 of the Party Wall etc. Act 1996, and Westminster City Council will want the NW8 ground and groundwater position set out.

Westminster housing stock: Grand Georgian and Regency terraces in Belgravia and Pimlico; Victorian and Edwardian mansion blocks; heritage-rich townhouses throughout; very high listed building density. Heritage-first planning approach; listed buildings on almost every street; basement and rear extension policies particularly strict. Read that before choosing a l shaped dormer route in Westminster — construction, not postcode, sets what is achievable.

Who decides a l shaped dormer on the edge of Westminster?

• Lambeth — adjoining Westminster, with 64 conservation areas centred on SE1. A l shaped dormer on the far side of the Westminster line is determined by Lambeth Council, so the Westminster quote for l shaped dormers is checked against Lambeth guidance before it is issued.
• City of London — adjoining Westminster, with 27 conservation areas centred on EC1. A l shaped dormer on the far side of the Westminster line is determined by City of London Corporation, so the Westminster quote for l shaped dormers is checked against City of London guidance before it is issued.
• Camden — the Camden boundary runs against Westminster, so a l shaped dormer a street from Westminster is decided by Camden Council instead. Camden runs 40 conservation areas across NW1 and its neighbours, which is why l shaped dormers priced for Westminster are re-checked against Camden policy whenever the Westminster address sits on that edge.
• Kensington and Chelsea — adjoining Westminster, with 38 conservation areas centred on SW1. A l shaped dormer on the far side of the Westminster line is determined by RBKC Planning, so the Westminster quote for l shaped dormers is checked against Kensington and Chelsea guidance before it is issued.

Sources for this Westminster l shaped dormer page: borough policies maps and conservation-area registers (2025–26), Royal Mail postcode district boundaries, the Town and Country Planning (Fees for Applications) (England) Regulations, the Town and Country Planning (General Permitted Development) (England) Order 2015 as amended, and the Party Wall etc. Act 1996.