W14 spans Hammersmith & Fulham and Kensington & Chelsea; conservation control is strong around Barons Court, and the Earls Court scheme borders the area.


Working across the whole borough rather than just this area? See mansard roof extensions in Hammersmith and Fulham.
A mansard roof extension adds a full storey behind a new sloping front face — a strong option on W14's terraces in West Kensington where a standard dormer is too small. Hammersmith & Fulham Council scrutinises mansards on townscape and precedent, especially within Barons Court, West Kensington, Edwardes Square / Scarsdale fringe; we design to the borough's roof guidance with a Heritage Statement where the setting requires it.
West Kensington's most space-efficient loft solution when PD-route dormers are blocked. Our chartered team designs mansards that get approved in West Kensington conservation areas — with heritage statements and planning officer negotiation built in.
Across West Kensington, Barons Court, Olympia, Holland Park fringe in W14, the dominant property is grand victorian terraces and mansion blocks around west kensington and barons court, with artists' studio houses near holland park. That stock shapes what mansard roof extensions looks like here: the right approach for a period terrace differs from a mansion-block flat or a new-build, and Hammersmith & Fulham Council judges each on design quality and neighbour impact. We survey the specific West Kensington property, confirm the planning route — Permitted Development, a Lawful Development Certificate, or full planning — and draw a council-ready set tailored to the W14 streetscape.
Housing stock in W14: Grand Victorian terraces and mansion blocks around West Kensington and Barons Court, with artists' studio houses near Holland Park.
Within the district: West Kensington, Barons Court, Olympia, Holland Park fringe.
Streets we know in W14: the Barons Court streets (Gledstanes Road, Castletown Road), the Gibbs Green area and the Edwardes Square fringe. Each road has its own building line, boundary treatment and precedent that Hammersmith & Fulham Council weighs when assessing a mansard roof extensions scheme.
Conservation areas: Barons Court, West Kensington, Edwardes Square / Scarsdale fringe. Inside these, most external work needs full planning and a Heritage Statement.
Getting around W14: West Kensington and Barons Court on the District and Piccadilly lines, plus Kensington Olympia.
Regeneration: West Kensington falls within or beside the Earls Court / West Kensington regeneration, which shapes local planning policy and design expectations.
Property values: around £550,000 for a flat and £1.2m-£2m for a house — a useful gauge of the build value an extension or loft adds in W14.
Borough character: Suburban-feel residential streets with strong conservation area coverage; well-established mansard precedents on many terraces.
We check against Hammersmith & Fulham Council's mansard design guide and design to match the terrace.
Required for West Kensington's conservation areas — demonstrates the mansard respects character and townscape.
Accurate photomontage showing how the mansard sits alongside neighbours — often decisive at Hammersmith & Fulham Council committee.
Mansards invariably trigger Party Wall notices in West Kensington's dense terraced streets. Structural package includes new ridge, tie beams, floor joists.
Full liaison with Hammersmith & Fulham Council planning officer, committee representation if called in.
Part L thermal, Part B fire (critical on mansards), Part E acoustic separation.
Single planning or building-regs submission.
Planning + building regs + structural.
Listed, conservation or complex sites.

Yes, but the handsome Victorian terraces around Gledstanes Road and Castletown Road sit in the Barons Court conservation area, so rear and side extensions and roof changes need full planning with a Heritage Statement rather than Permitted Development. We design to match the period detailing and submit to Hammersmith & Fulham.
W14 straddles the boundary — West Kensington and Barons Court largely sit in Hammersmith & Fulham, with the eastern edge toward Holland Park in Kensington & Chelsea. The two councils apply different conservation and basement controls, so we confirm your exact authority before quoting.
The major Earls Court / West Kensington regeneration borders W14, bringing thousands of new homes and improved public realm, supporting values. For a house project the binding controls remain Permitted Development limits and the local conservation area, which we check for your address.
Yes. The mansion blocks around West Kensington and Olympia usually have freeholder controls alongside council planning, and any external change needs full consent. We produce drawings that satisfy both the freeholder and the council, and handle Party Wall matters between flats.
With West Kensington property at around £550,000 for a flat and £1.2m-£2m for a house, the professional drawing fee is a small fraction of the value the work adds to W14's grand victorian terraces and mansion blocks around. Hammersmith & Fulham Council charges its own statutory application fee on top (currently £548 for a householder planning application, £610 for a full application). We quote the drawings as one fixed price and the free site survey covers every W14 address.
For a W14 project across West Kensington, Barons Court, Olympia, Holland Park fringe, expect roughly 3–4 weeks from instruction to submission: week 1 the measured survey, weeks 2–3 the drawings and your revisions, then validation and the statutory determination by Hammersmith & Fulham Council (8 weeks for a householder application). We carry the West Kensington application through every officer query to the decision.
West Kensington (W14) sits primarily in Hammersmith and Fulham, so applications are decided by Hammersmith & Fulham Council. Conservation areas within W14 include Barons Court, West Kensington, Edwardes Square / Scarsdale fringe, where full planning and a Heritage Statement are required. We confirm the planning route for your exact address before quoting.
Almost always. Any structural work behind mansard roof extensions in West Kensington — new openings, steel beams, loft floors, foundations — needs Building Regulations approval covering structure (Part A), fire escape (Part B) and insulation (Part L), submitted to Hammersmith & Fulham Council Building Control or an approved inspector. On W14's typically terraced and semi-detached stock, a Party Wall notice to adjoining neighbours is normally required before the steelwork. We coordinate both as part of the Complete package.
In value terms, yes. With West Kensington (W14) property at around £550, 000 for a flat and £1.2m-£2m for a house, a well-designed extension or loft typically returns more than it costs in added floor area and sale value. The bigger risk is an unapproved or non-compliant scheme — which is why council-ready drawings and a clean Building Control sign-off matter on W14 homes.
If your site sits close to the edge of the borough, it is worth checking the authority next door. Browse everything we do in SW6, W6 and W12.
Pick a slot that suits you. No obligation and no sales pressure, just straight answers on your planning route.
Every W14 postcode district we draw in, the stock that dominates it and the authority that validates a mansard roof extension there. W14 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 |
|---|---|---|---|
| W14 | West Kensington / Barons Court | Victorian and Edwardian villas | W14 straddles a boundary: West Kensington / Barons Court addresses fall to Hammersmith & Fulham Council or RBKC Planning, so confirm which authority validates the mansard roof extension before submitting W14 drawings. |
| W14 | Barons Court | Edwardian mansion blocks, Victorian terraces | Barons Court sits inside W14; mansard roof extension proposals here are determined by Hammersmith & Fulham Council. |
| W14 | Holland Park | Victorian and Edwardian villas | Holland Park sits inside W14; mansard roof extension proposals here are determined by RBKC Planning. |
| SW6 | Fulham / Parsons Green | Victorian terraces, mansion blocks | Adjoining district to W14, also inside Hammersmith and Fulham for mansard roof extension purposes. |
| W6 | Hammersmith / Brackenbury Village | Victorian terraces, mansion blocks | Adjoining district to W14, also inside Hammersmith and Fulham for mansard roof extension purposes. |
| W12 | Shepherd's Bush / White City | Victorian and Edwardian terraces | Adjoining district to W14, also inside Hammersmith and Fulham for mansard roof extension purposes. |
| SW3 | Chelsea / Brompton | Georgian and Victorian terraces, listed buildings | Adjoining district to W14, also inside Kensington and Chelsea for mansard roof extension purposes. |
| SW5 | Earl's Court | Stucco terraces, Edwardian mansion blocks | Adjoining district to W14, also inside Kensington and Chelsea for mansard roof extension purposes. |
| SW7 | South Kensington / Knightsbridge | Stucco terraces, mansion blocks, listed buildings | Adjoining district to W14, also inside Kensington and Chelsea for mansard roof extension purposes. |
| SW10 | West Brompton / World's End | Georgian and Victorian terraces, listed buildings | Adjoining district to W14, also inside Kensington and Chelsea for mansard roof extension purposes. |
Roof pitch, wall build-up and plot depth change every few W14 streets, and each one changes what a mansard roof extension can achieve at that address.
How designation changes a W14 (West Kensington / Barons Court) mansard roof extension: Hammersmith & Fulham Council maintains 45 conservation areas, including Brackenbury Village, Fulham Palace Road, Parsons Green. Inside any of them a W14 (West Kensington / Barons Court) mansard roof extension cannot rely on permitted development, and the route becomes a £548 householder application determined in 8 weeks rather than a £249 prior approval in 6 weeks. Brackenbury Village sets the tone for W14 (West Kensington / Barons Court) casework.
Article 4 and your W14 (West Kensington / Barons Court) mansard roof extension: Article 4 removes PD for HMO conversions; restrictions on ground-floor shop-to-residential in certain streets. At a W14 address that matters twice over, because Hammersmith & Fulham Council applies the direction unevenly across W14 (West Kensington / Barons Court) — we read the W14 (West Kensington / Barons Court) policies map for the exact W14 address before quoting mansard roof extensions.
What W14 (West Kensington / Barons Court) is built from: Victorian and Edwardian terraces — particularly two-storey bay-fronted terraces south of the river in Fulham and Parsons Green; mansion blocks along main roads. Suburban-feel residential streets with strong conservation area coverage; well-established mansard precedents on many terraces. That mix decides the mansard roof extension route in W14 (West Kensington / Barons Court) more than the postcode does, and it is what a Hammersmith & Fulham Council case officer reads first. A householder application costs £548 paid to Hammersmith & Fulham Council direct, with 8 weeks to a decision once validated.
How designation changes a W14 (West Kensington / Barons Court) mansard roof extension: RBKC Planning maintains 38 conservation areas, including Chelsea, Notting Hill, Holland Park. Inside any of them a W14 (West Kensington / Barons Court) mansard roof extension cannot rely on permitted development, and the route becomes a £548 householder application determined in 8 weeks rather than a £249 prior approval in 6 weeks. Chelsea sets the tone for W14 (West Kensington / Barons Court) casework.
Article 4 and your W14 (West Kensington / Barons Court) mansard roof extension: Article 4 Directions covering HMOs, office-to-residential, and basement developments — RBKC has some of the strictest basement policies in London. At a W14 address that matters twice over, because RBKC Planning applies the direction unevenly across W14 (West Kensington / Barons Court) — we read the W14 (West Kensington / Barons Court) policies map for the exact W14 address before quoting mansard roof extensions.
Digging below a W14 (West Kensington / Barons Court) property: RBKC's basement policy (post-2015) limits to single-storey under 50% of garden area; double-storey basements effectively prohibited in residential streets. Where a mansard roof extension in W14 (West Kensington / Barons Court) involves excavation that is read beside the Party Wall etc. Act 1996, which needs two months notice for a W14 (West Kensington / Barons Court) dig within 3 m of a neighbour, and RBKC Planning expects the W14 ground conditions addressed in the application.
What W14 (West Kensington / Barons Court) is built from: Grand white stucco Regency and Victorian terraces; red-brick Queen Anne mansions in Kensington; Edwardian mansion blocks; almost no post-war housing stock. Internationally wealthy residents; extensive listed building coverage; heritage and streetscape prioritised in every decision. That mix decides the mansard roof extension route in W14 (West Kensington / Barons Court) more than the postcode does, and it is what a RBKC Planning case officer reads first. A householder application costs £548 paid to RBKC Planning direct, with 8 weeks to a decision once validated.
Sources for this W14 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.
Free fixed quote in 60 seconds. MCIAT chartered.
Get my free quote →Or contact us about your project firstYou can search by service or borough to find the right fit, or set up your account to track your project. When you are ready, get a quote for your project — most homeowners have a fee in minutes — or contact us and a chartered technologist will be in touch.