Which West Hampstead postcodes does this mansard roof extension service cover?
Every West Hampstead postcode district we draw in, the stock that dominates
it and the authority that validates a mansard roof extension there. West Hampstead fees below are the
statutory England rates for 2026, not mansard roof extension estimates.
| Postcode | Area | Dominant stock | What it means for a mansard roof extension |
|---|
| NW6 | Kilburn / West Hampstead / Queen's Park | Edwardian mansion blocks, Victorian villas | A mansard roof extension in Kilburn / West Hampstead / Queen's Park may land with Camden Council or Brent Council — NW6 crosses the boundary, and the NW6 policies map decides it street by street. |
| NW1 | Camden Town | Victorian terraces, mansion blocks | Neighbouring Camden Town, where mansard roof extension work is handled by the same Camden Council case officers. |
| NW3 | Hampstead | Georgian and Victorian villas, listed buildings | Neighbouring Hampstead, where mansard roof extension work is handled by the same Camden Council case officers. |
| NW1 | Primrose Hill | Victorian and Edwardian terraces | Neighbouring Primrose Hill, where mansard roof extension work is handled by the same Camden Council case officers. |
| NW5 | Kentish Town | Victorian terraces | Neighbouring Kentish Town, where mansard roof extension work is handled by the same Camden Council case officers. |
| NW3 | Belsize Park | Edwardian mansion blocks, Victorian villas | Neighbouring Belsize Park, where mansard roof extension work is handled by the same Camden Council case officers. |
| WC1 | Bloomsbury | Georgian terraces, listed buildings | Neighbouring Bloomsbury, where mansard roof extension work is handled by the same Camden Council case officers. |
| W1T | Fitzrovia | Georgian terraces, Victorian mansion blocks | Neighbouring Fitzrovia, where mansard roof extension work is handled by the same Camden Council case officers. |
| N1C | King's Cross | Modern apartments, converted warehouses | Neighbouring King's Cross, where mansard roof extension work is handled by the same Camden Council case officers. |
| N6 | Highgate | Georgian villas, Victorian and Edwardian semis | Neighbouring Highgate, where mansard roof extension work is handled by the same Camden Council case officers. |
| NW3 | Swiss Cottage | Mansion blocks, post-war flats | Neighbouring Swiss Cottage, where mansard roof extension work is handled by the same Camden Council case officers. |
| NW5 | Gospel Oak | Victorian terraces, post-war estates | Neighbouring Gospel Oak, where mansard roof extension work is handled by the same Camden Council case officers. |
How does a mansard roof extension differ street by street across West Hampstead?
Roof pitch, wall build-up and plot depth change every few West Hampstead
streets, and each one changes what a mansard roof extension can achieve at that address.
- West Hampstead (NW6) — mansard roof extension work in West Hampstead means edwardian mansion blocks, victorian villas. West Hampstead is Victorian and Edwardian villa streets. A mansard on a Victorian terrace almost always needs full planning permission throughout NW6. Camden Council decides the West Hampstead application, and West Hampstead Thameslink anchors the West Hampstead location plan.
- Near West Hampstead: Kentish Town (NW5) — a mansard roof extension in Kentish Town starts from victorian terraces, and Kentish Town reads as Victorian terraced streets, gentrifying. A mansard on a Victorian terrace almost always needs full planning permission in NW5. Camden Council assesses Kentish Town mansard roof extensions against its own Kentish Town character guidance, and the location plan we draw for Kentish Town references Kentish Town City Farm.
- Near West Hampstead: Belsize Park (NW3) — mansard roof extension work in Belsize Park means edwardian mansion blocks, victorian villas. Belsize Park is tree-lined avenues, Edwardian mansion blocks. A mansard on a Victorian terrace almost always needs full planning permission throughout NW3. Camden Council decides the Belsize Park application, and Belsize Park station anchors the Belsize Park location plan.
- Near West Hampstead: Bloomsbury (WC1) — mansard roof extension work in Bloomsbury means georgian terraces, listed buildings. Bloomsbury is Georgian squares, academic. Mansards read as original on Georgian terraces throughout WC1. Camden Council decides the Bloomsbury application, and British Museum anchors the Bloomsbury location plan.
- Near West Hampstead: Fitzrovia (W1T) — mansard roof extension work in Fitzrovia means georgian terraces, victorian mansion blocks. Fitzrovia is Georgian and Victorian mix, creative quarter. Mansards read as original on Georgian terraces throughout W1T. Camden Council decides the Fitzrovia application, and Fitzroy Square anchors the Fitzrovia location plan.
- Near West Hampstead: King's Cross (N1C) — regenerated quarter, contemporary new-build defines King's Cross, where modern apartments, converted warehouses set what a mansard roof extension can do. Mansards on modern buildings are unusual and generally read as an alien addition across N1C. Any King's Cross mansard roof extension is validated by Camden Council, with King's Cross Station the usual King's Cross reference point on the site plan.
- Near West Hampstead: Highgate (N6) — mansard roof extension work in Highgate means georgian villas, victorian and edwardian semis. Highgate is village character on the hill, Georgian and Victorian. Mansards read as original on Georgian terraces throughout N6. Camden Council decides the Highgate application, and Highgate Cemetery anchors the Highgate location plan.
Does West Hampstead planning policy restrict a mansard roof extension?
West Hampstead conservation designations: there are 40 across Camden Council, Hampstead, Primrose Hill, Bloomsbury among them. Designation costs a West Hampstead owner the permitted-development route: a mansard roof extension then needs a £548 householder application over 8 weeks, in place of the £249 prior approval route that takes 6 weeks. Camden Town is the West Hampstead designation that most often changes a mansard roof extension design.
What Article 4 removes near West Hampstead: Article 4 removes permitted development for HMO conversions (C3 to C4) across the borough, plus restrictions on basement extensions in 12 conservation areas. Before pricing a mansard roof extension we check whether the NW6 address is inside the mapped area, because Camden Council draws the West Hampstead boundary street by street rather than across the whole of West Hampstead.
Digging below a West Hampstead property: Camden's basement policy (Policy A5) restricts single-storey basements to 50% of garden area; double-storey basements generally refused outside commercial zones. Where a mansard roof extension in West Hampstead involves excavation that is read beside the Party Wall etc. Act 1996, which needs two months notice for a West Hampstead dig within 3 m of a neighbour, and Camden Council expects the NW6 ground conditions addressed in the application.
The building fabric around West Hampstead: Victorian and Edwardian terraces, Georgian townhouses in Bloomsbury and Hampstead, post-war mansion blocks, modern developments in King's Cross. Creative, affluent in Hampstead and Primrose Hill; dense mixed-use around Camden Town and Kings Cross; academic character in Bloomsbury. A mansard roof extension in West Hampstead is scoped against that stock first, because it decides whether the scheme runs as permitted development, a £274 Lawful Development Certificate, or a full £548 application to Camden Council.
Who decides a mansard roof extension on the edge of West Hampstead?
- Westminster — adjoining West Hampstead, with 56 conservation areas centred on SW1. A mansard roof extension on the far side of the West Hampstead line is determined by Westminster City Council, so the West Hampstead quote for mansard roof extensions is checked against Westminster guidance before it is issued.
- Islington — adjoining West Hampstead, with 40 conservation areas centred on N1. A mansard roof extension on the far side of the West Hampstead line is determined by Islington Council, so the West Hampstead quote for mansard roof extensions is checked against Islington guidance before it is issued.
- Barnet — the Barnet boundary runs against Camden, so a mansard roof extension a street from West Hampstead is decided by Barnet Council instead. Barnet runs 20 conservation areas across N2 and its neighbours, which is why mansard roof extensions priced for West Hampstead are re-checked against Barnet policy whenever the West Hampstead address sits on that edge.
- Haringey — the Haringey boundary runs against Camden, so a mansard roof extension a street from West Hampstead is decided by Haringey Council instead. Haringey runs 29 conservation areas across N4 and its neighbours, which is why mansard roof extensions priced for West Hampstead are re-checked against Haringey policy whenever the West Hampstead address sits on that edge.
Sources for this West Hampstead mansard roof extension 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.
