
Basement Conversion Drawings in West Kensington W14
Fixed-fee, MCIAT-chartered basement conversion drawings for West Kensington (W14) homeowners — London Borough of Hammersmith & Fulham validation and local constraints handled from the start.
West Kensington (W14) is defined by its red-brick Victorian mansion flats — the Gunter family developed much of the district as planned mansion-block and terrace streets, and a large share of the housing is now flats rather than whole houses. That tenure shapes every project: rear, roof and party-wall work here typically touches more than one household.
The Gunter Estate, Barons Court and Sinclair Road conservation areas cover much of the district and protect that planned red-brick character. We establish the conservation boundary, the tenure and the block's shared elements before recommending a route, and draw to the borough's guidance.


Planning in West Kensington (W14): what to know before you apply
W14 sits across the Gunter Estate, Barons Court and Sinclair Road conservation areas, which protect the planned red-brick mansion-flat streets and remove permitted development rights on many of them — and because so much of the stock is flatted, extensions and loft work are assessed against shared roofs, rear elevations and party walls as well as conservation character. London Borough of Hammersmith and Fulham does not publish an Article 4 schedule to the national open-data register, so an empty entry there is not evidence of absence — we confirm the current directions with the council before advising.
Typical West Kensington housing stock
Red-brick late-Victorian mansion flats and tall terraced houses laid out by the Gunter estate, many now subdivided into flats, with further mansion blocks toward Barons Court.
Streets we regularly draw for in West Kensington
Gunterstone Road · Comeragh Road · Gledstanes Road · Sinclair Road · North End Road
What W14 is actually built of
Measured from 412 classified residential buildings in W14, not from a description of the area.
West Kensington W14 housing mix
Residential building form across the W14 postcode district, from 412 classified buildings.
| Attached on more than one side | 78% |
|---|---|
| Attached on one side | 19% |
| Detached | 3% |
| Median building footprint | 74 m² |
| Addresses per buildingAbove about 2 means flats and maisonettes dominate | 3.83 |
| Buildings classified | 412 |
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 2026-08-17.
Basement Conversion Drawings for West Kensington (W14) homes: the package and the process
A basement package is led by its section. It has to show the existing structure, the proposed floor level, retained or underpinned walls, the tanking system, and how the finished room achieves head height without undermining what sits above. Structural design and architectural design are drawn together because here they are the same decision.
Habitable basement rooms also need light, ventilation and escape. The drawings set out lightwells and their guarding, mechanical ventilation where natural is not achievable, and an escape route that Building Control will accept — usually a protected stair, sometimes an external route out of the lightwell.
What sits below the house decides the route. An existing cellar under a Victorian terrace is a conversion with a known volume, while a house with no cellar is a dig-out with underpinning, structural design and a very different drawing set — and the two are rarely interchangeable.
Do I need planning permission for a basement conversion in London?
An internal conversion of an existing cellar — new floor, insulation, a habitable layout — often does not need planning permission, because the works sit entirely within the existing structure and do not change its external appearance. Digging out a new basement, lowering an existing floor to gain headroom, or enlarging the footprint under a garden usually does, particularly where excavation extends beyond the existing building line. Any external alteration needed to serve the basement — a front light well, a sunken external staircase, or altering the pavement or front garden — is also likely to need planning permission in its own right, even when the basement works themselves would not. In a conservation area, a front light well tends to draw closer scrutiny than the same feature elsewhere, since it changes the street-facing elevation and the pavement it sits within — one more reason we assess the whole scheme, not just the room below ground, before recommending a route.
Cellar conversion or new dig-out — which route fits your property?
The two starting points lead to very different drawing sets. A cellar conversion works with a void that already exists: the drawings focus on damp-proofing, insulation, headroom, natural or borrowed light, means of escape and a compliant layout, coordinated with building regulations rather than planning.
A new dig-out or floor-lowering project starts from a structural decision — how the existing foundations will be underpinned to allow excavation beneath them — and the drawings and structural calculations are produced together from the outset, since the sequence of underpinning, temporary works and waterproofing has to be engineered before a builder can safely start.
What structural design does underpinning a basement need?
Lowering a floor or digging a new basement beneath an existing house means underpinning its foundations in sequenced sections, so the building above stays supported throughout. We produce the structural drawings and calculations for the underpinning sequence, any new steel beams or retaining walls, and the interaction with neighbouring foundations, in-house as part of the same package — so your structural engineer sign-off and your architectural drawings are never out of step with each other.
The sequencing matters as much as the sizing: underpinning is dug and cast in short, alternating sections so the existing wall is never left unsupported over any significant length, and the drawings set out the order those sections are worked in alongside the retaining and waterproofing detail. Getting that sequence wrong is one of the most common causes of cracking and delay on a basement project, which is why we treat it as a design decision rather than something left for the contractor to work out on site.
| Route | Typical scope | Planning position | Fee from |
|---|---|---|---|
| Existing cellar conversion | Fit-out of an existing void, no excavation | Usually building regulations only | £2,400 |
| Floor lowering / partial dig-out | Increases headroom within the existing footprint | Often needs planning permission | £3,200 |
| New-build basement or light well extension | New basement area beyond the existing footprint | Full planning plus Party Wall Act | £3,850 |

Basement Conversion Drawings in West Kensington W14 — FAQs
How much do basement conversion drawings cost in London?+
Does a basement conversion need planning permission?+
Will I need a party wall agreement for a basement conversion?+
Are structural calculations included in a basement conversion package?+
Do I need an architect for a basement conversion?+
Do I need planning permission for a side-return extension in Hammersmith & Fulham?+
Will I need a Basement Impact Assessment for a basement in Hammersmith & Fulham?+
What is special about the Peterborough Estate 'Lion houses'?+
How long does Hammersmith & Fulham take to decide?+
How much do planning drawings cost in Hammersmith & Fulham?+
Get your free West Kensington planning assessment
Tell us your West Kensington (W14) address and ambition — we'll confirm feasibility, local constraints and a fixed fee within one working day.