Flat Conversions Barnes

Flat conversions in Barnes start with the building. 52% of homes here are houses, 33% of all homes are terraced, and 51% were built before 1919, so the likely candidates are the larger period houses. Richmond's Local Plan says only certain types of property are suitable for conversion to flats and some areas would be incompatible with conversions, so suitability is tested before design, and splitting a house into flats needs planning permission. We build conversions to the approved drawings: new separating floors and walls, fire protection, services split per flat, and the kitchen and bathroom each flat needs.

In Barnes, 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 Barnes: 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 Barnes houses suit conversion under Richmond policy

Richmond Local Plan Policy 14, on loss of housing, says proposals for conversions should assess the suitability of the property and environmental and design considerations. The Local Plan also says only certain types of property are suitable for conversion to flats. In Barnes that points to larger houses with enough floor area and height for each new flat to meet the space standards, rather than small period cottages. The owner's designer or planning agent makes that case in the application; we price and programme against the drawings that result.

The London Plan small sites supporting text lists residential conversions among the forms of incremental intensification that count where they result in net additional housing. For a Barnes owner that is the policy backdrop: a well-planned conversion adds homes without new building. The detail still decides it, from bin and cycle storage in the front garden to how the entrance is shared. We look at those practical points on the survey, because they affect how the ground floor is laid out and where the new service runs go.

Housing in Barnes

On the valuation list Barnes counts about 9,740 homes, 48% flats and 52% houses; 51% predate 1919, 17% are interwar and 31% post-war. A converted terrace in Barnes has two party walls to consider for sound, and 33% of homes here are terraced.

Space standards every new Barnes flat has to meet

Richmond's Local Plan adopts the Nationally Described Space Standard, and London Plan Policy D6 applies minimum space standards to all self-contained residential accommodation, with conversions counted as new dwellings. Under Policy D6 a one-bedspace single bedroom must be at least 7.5 square metres and 2.15m wide, and a double or twin bedroom at least 11.5 square metres. In a Barnes period house the front rooms on the upper floors can meet that; the smaller back rooms may not, which shapes where each flat's bedrooms go.

Policy D6 also sets a minimum floor to ceiling height of 2.5m for at least 75 per cent of the Gross Internal Area of each dwelling. In a Barnes period house the main ground and first floor rooms often clear it; the top floor and the back addition, with lower ceilings, are where a flat can fall short. GOV.UK notes that the Nationally Described Space Standard is not a building regulation and sits solely within the planning system, so it is fixed at design stage. We build to the heights and room sizes on the approved drawings and flag any clash early.

Fire and sound separation between Barnes flats

Turning a Barnes house into flats is a material change of use under the Building Regulations, which brings Part B fire separation between flats, a protected escape route, fire doors and linked alarms. Part L energy and the access requirements also apply to the new flats as building control sets them. The old timber floors between storeys are upgraded with fire-resisting ceilings and insulation, and the shared hall and stair become the protected route. We plan those details with the building control surveyor before strip out, because they affect ceiling heights, door positions and where the service risers can run through the house.

For sound, Part E applies, and Approved Document E sets lower performance for dwelling-houses and flats formed by material change of use: 43 dB airborne for walls and for floors and stairs, and 64 dB maximum impact for floors and stairs. In a Barnes conversion the floors are the hard part, because the original joists carry the new flat's floor above and the ceiling below. Resilient bars, dense boards, acoustic insulation and a floating floor on top make up the build-up, and testing before completion shows whether it passes.

Services, addresses and neighbours in a Barnes flat conversion

Each new flat in a Barnes conversion needs its own supplies: a separate electricity meter and consumer unit, its own heating and hot water, and usually a separate gas meter or an all-electric system. Water may stay on a shared supply with sub-metering or be split. The utilities will not connect new meters until each flat has an address, so the owner applies to Richmond for street naming and numbering early. We plan the meter positions and risers on the approved drawings before strip out.

Where the conversion cuts into a party wall for steel bearings or builds on it, the Party Wall Act applies, and the building owner serves the notices on the neighbours. In a Barnes terrace it can arise at the back addition, where new steels bear on the shared wall. Going 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. On a reversal we strip out the second kitchen and reconnect the house on single services.

• Separating walls built and lined for sound between flats
• House to flat conversions into two or more self-contained units
• Protected escape stairs and fire-rated flat entrance doors

VOA Council Tax stock of properties, March 2025, for North Barnes and Mortlake & South Barnes. Counts rounded by the VOA.

If this is your first project in Barnes, these are worth a look: structural alterations in Barnes, flat conversions across Richmond upon Thames, a building contractor for the whole conversion, refurbishing a flat that has already been converted, our London flat conversions page and Structural Engineer Report Cost.

Trusted Flat Conversions in Barnes

Converting a Barnes house into flats puts structure, fire safety, acoustics and services into one tight sequence. GS Renovation builds that sequence as one firm, led by the founder and director Abdelaaziz Saaid, working to the planning consent and building regulations approval the owner or their designer has obtained. We set out separating floors, risers and escape routes with the building control surveyor before strip out, keep to a written programme, and pass on the test results and certificates each flat needs for sale or letting.

• Separate meters, supplies and consumer units arranged for every flat
• Mains-wired, interlinked smoke and heat alarms to the approved fire strategy
• Materials priced at options, so you choose the finish

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.