Loft Conversion Drawings in Westminster

Which postcode districts around Westminster do we cover for loft conversion work?

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

How does a loft conversion 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 loft conversion can achieve at that address.

• Mayfair (W1J, W1K) — a loft conversion in Mayfair starts from georgian townhouses, listed buildings, and Mayfair reads as Georgian listed townhouses, luxury. Georgian roofs here are shallow and often behind a parapet in W1J. Westminster City Council assesses Mayfair loft conversions 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 loft conversion can do. The Victorian butterfly and double-pitched roofs on these streets normally clear the 2.2 m head height a dormer conversion needs once the ceiling joists are raised across SW1X. Any Belgravia loft conversion is validated by Westminster City Council, with Eaton Square the usual Belgravia reference point on the site plan.
• Marylebone (W1U, W1G, W1H) — a loft conversion in Marylebone starts from georgian terraces, edwardian mansion blocks, and Marylebone reads as Georgian and Victorian terraces, mansion blocks. Georgian roofs here are shallow and often behind a parapet in W1U. Westminster City Council assesses Marylebone loft conversions against its own Marylebone character guidance, and the location plan we draw for Marylebone references Marylebone High Street.
• Pimlico (SW1V) — loft conversion work in Pimlico means regency terraces, post-war estates. Pimlico is Regency stucco terraces, grid plan. Post-war roofs on these estates are often trussed throughout SW1V. Westminster City Council decides the Pimlico application, and Tate Britain anchors the Pimlico location plan.
• Soho (W1D, W1F) — a loft conversion in Soho starts from georgian terraces, mixed-use, and Soho reads as Georgian fragments, mixed-use. Georgian roofs here are shallow and often behind a parapet in W1D. Westminster City Council assesses Soho loft conversions against its own Soho character guidance, and the location plan we draw for Soho references Soho Square.
• Covent Garden (WC2E, WC2H) — loft conversion work in Covent Garden means georgian terraces, conversions. Covent Garden is Georgian piazza, listed buildings. Georgian roofs here are shallow and often behind a parapet throughout WC2E. Westminster City Council decides the Covent Garden application, and Royal Opera House anchors the Covent Garden location plan.
• St John's Wood (NW8) — loft conversion work in St John's Wood means victorian villas, mansion blocks. St John's Wood is Victorian villas, mansion blocks. The Victorian butterfly and double-pitched roofs on these streets normally clear the 2.2 m head height a dormer conversion needs once the ceiling joists are raised throughout NW8. Westminster City Council decides the St John's Wood application, and Lord's Cricket Ground anchors the St John's Wood location plan.

What local planning policy applies to a loft conversion in Westminster?

Westminster conservation designations: there are 56 across Westminster City Council, Mayfair, Belgravia, Marylebone among them. Designation costs a Westminster owner the permitted-development route: a loft conversion then needs a £548 householder application over 8 weeks, in place of the £249 prior approval route that takes 6 weeks. Marylebone is the Westminster designation that most often changes a loft conversion design.

Article 4 and your Westminster loft conversion: Multiple Article 4 Directions — office-to-residential restrictions, HMO conversions, retail to residential in shopping zones. At a NW8 address that matters twice over, because Westminster City Council applies the direction unevenly across Westminster — we read the Westminster policies map for the exact NW8 address before quoting loft conversions.

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 loft conversion 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.

What Westminster is built from: 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. That mix decides the loft conversion route in Westminster more than the postcode does, and it is what a Westminster City Council case officer reads first. A householder application costs £548 paid to Westminster City Council direct, with 8 weeks to a decision once validated.

Who decides a loft conversion on the edge of Westminster?

• City of London — the City of London boundary runs against Westminster, so a loft conversion a street from Westminster is decided by City of London Corporation instead. City of London runs 27 conservation areas across EC1 and its neighbours, which is why loft conversions priced for Westminster are re-checked against City of London policy whenever the Westminster address sits on that edge.
• Camden — the Camden boundary runs against Westminster, so a loft conversion a street from Westminster is decided by Camden Council instead. Camden runs 40 conservation areas across NW1 and its neighbours, which is why loft conversions priced for Westminster are re-checked against Camden policy whenever the Westminster address sits on that edge.
• Kensington and Chelsea — cross the Westminster boundary and RBKC Planning takes the loft conversion instead, applying 38 conservation areas of its own around SW1. We re-price loft conversions at the Westminster edge because Kensington and Chelsea policy and Westminster policy rarely align on loft conversion depth.
• Wandsworth — the Wandsworth boundary runs against Westminster, so a loft conversion a street from Westminster is decided by Wandsworth Council instead. Wandsworth runs 45 conservation areas across SW8 and its neighbours, which is why loft conversions priced for Westminster are re-checked against Wandsworth policy whenever the Westminster address sits on that edge.

Sources for this Westminster loft conversion 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.