Flat Conversions Richmond

Splitting a house into self-contained flats needs planning permission, and in Richmond upon Thames policy steers it tightly. Richmond's Local Plan says only certain types of property are suitable for conversion to flats and that some areas would be incompatible with conversions, and it adopts the Nationally Described Space Standard for the new homes. We build conversions to an approved scheme: the separating floors and walls, fire protection, new kitchens and bathrooms, and a separate set of services for each flat. We also take converted houses back to one family home where consent allows.

In Richmond upon Thames, converting a house into two or three flats is published at £50,000 to £120,000 including professional and council fees, and an England-wide guide puts a straightforward two-flat split at £40,000 to £80,000 in construction alone, which is the part a builder prices (indicative London ranges, Architectural Drawings and Mayfair Studio, 2026). GS Renovation Ltd, a building contractor based in Potters Bar, does the work in Richmond upon Thames: we build the conversion to the approved drawings, building control inspects the fire and sound separation, and a registered electrician certifies each flat's electrics.

Which Richmond upon Thames houses suit conversion to flats

Suitability is the first question, and Richmond puts it in policy. Local Plan Policy 14 (Loss of Housing) says conversion proposals should assess the suitability of the property along with environmental and design considerations. The Local Plan also says only certain types of property are suitable while some areas would be incompatible with conversions. In practice that tends to favour larger houses with generous floor plans rather than small two up, two down cottages in Richmond upon Thames.

For the build, a suitable house is one where each flat can have its own front door off a shared hall, stacked kitchens and bathrooms so soil stacks run straight down, and room for a protected stair. With 38% of the borough's homes built before 1919, likely candidates include tall period houses on several floors. We look at the existing floor structure, the stair width and the drain runs before your designer finalises the layout, because moving a stack later costs time on every floor.

Housing in Richmond upon Thames

Of the 85,810 homes the valuation list records in Richmond upon Thames, 38% were built before 1919, 24% between the wars and 37% since 1945; 42% are flats and 58% are houses. A converted terrace in Richmond upon Thames has two party walls to consider for sound, and 29% of homes here are terraced.

Space standards for new flats in Richmond upon Thames

Every flat created in Richmond upon Thames has minimum sizes to meet. Richmond's Local Plan adopts the Nationally Described Space Standard, and the London Plan space standards table says a new dwelling includes conversions. These are planning standards, not building regulations, so they are fixed when consent is granted and the build has to deliver them. Under London Plan Policy D6 a single bedroom must be at least 2.15m wide with an area of at least 7.5 sq.m. A double or twin bedroom needs at least 11.5 sq.m.

Ceiling height is where period houses catch owners out. Policy D6 sets a minimum floor to ceiling height of 2.5m for at least 75 per cent of each dwelling's gross internal area, which a tall Victorian ground floor can meet but a top floor under the roof may not. We measure every room against the approved drawings before partitions go up, so a bedroom that falls short is caught at setting out rather than at completion.

Fire separation and sound insulation between Richmond upon Thames flats

Between flats, sound and fire separation drive the build detail. Approved Document E sets lower sound insulation performance for flats formed by material change of use: 43 dB airborne for walls, floors and stairs, and 64 dB maximum impact for floors and stairs. In a Richmond upon Thames house with timber floors, that means resilient ceilings, mineral wool in the joists and careful sealing around pipes, followed by the pre-completion sound test required for flats formed this way.

Part B fire separation of the same floors and walls is designed alongside. Each flat becomes its own fire compartment, so the floors between them need a set period of fire resistance, service penetrations are fire stopped, and the shared stair becomes a protected escape route with fire doors and self closers onto it. Detection is interlinked within each flat and often in the common parts. We build these details before the ceilings are closed, because building control inspects them open.

Meters, addresses and turning Richmond upon Thames flats back into a house

Each new flat needs its own services and its own address. That means separate electricity and gas supplies with their own meters, a water supply that can be isolated per flat, and heating and hot water independent of the neighbours. The owner applies to the council for street naming and numbering so each flat can be registered with the utilities. Where the conversion cuts into or builds on a party wall, the owner serves notice under the Party Wall Act. On a mid-terrace house that means neighbours on both sides, so the notices go out well before the start date.

Some owners go the other way. Richmond only accepts reverting converted flats back to a single house where the property was originally built as a single family dwelling house and other tests are met. When that consent is in place, the work is removing the extra kitchens and entrance doors, merging the services onto one supply, and opening up the stair so the house reads as one home again. Any sound insulation added earlier can often stay.

• Separate gas, electricity and water supplies for each flat
• A kitchen and shower room fitted in every new flat
• Heating and hot water for each flat, gas by a Gas Safe registered engineer

VOA Council Tax stock of properties, March 2025, for all 23 statistical areas in Richmond upon Thames. Counts rounded by the VOA.

Plenty of Richmond upon Thames projects start with one job and grow, so it helps to see structural alterations in Richmond upon Thames, our Richmond upon Thames area guide, builders in Richmond upon Thames, party walls in a flat conversion, flat conversions across London and Structural Engineer Report Cost.

The GS Renovation Difference in Richmond upon Thames

Conversions involve structure, fire, sound, drainage and several sets of services at once, and the work has to match the approved drawings room by room. We price from those drawings, check the stair, stacks and floors on site before starting, and give a written programme showing when each sound test and inspection falls. A registered electrician certifies the electrics and an engineer on the Gas Safe Register does the gas work. The founder has more than three decades of hands-on building experience.

• Full plans application to building control, never a building notice
• Mains-wired, interlinked smoke and heat alarms to the approved fire strategy
• Structural engineer instructed and coordinated on your behalf

Checked by Abdelaaziz Saaid, founder and director of GS Renovation Ltd (Companies House no. 14611254). Structural design is by the consulting engineer appointed to your project.