Flat Conversions Bexley

Flat conversions in Bexley turn a house into self-contained flats, or put flats back together as one house. With 73% of homes in the borough houses and 27% flats, the candidates are family houses, from older terraces to interwar semis. Splitting a house into flats always needs planning permission, and Bexley's Design Guide SPD Part 2 sets out what a conversion must achieve on space, appearance and amenity. We build the approved scheme, with the fire and sound separation and separate services that turn one house into separate homes.

In Bexley, 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 Bexley: 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.

Planning permission and Bexley's conversion policy

Every house to flats conversion in Bexley needs planning permission, because it creates new dwellings. Bexley's Design Guide SPD Part 2 code B 12 requires the conversion to achieve appropriate internal space standards and to avoid unacceptable impacts on the streetscape or the amenity of the local area. The London Plan lists residential conversions among the forms of incremental intensification that count where they result in net additional housing, so the principle can be supported, but the detail decides the outcome. Your designer or agent prepares and submits the application.

Two further consequences follow from creating new homes. Bexley states that development creating a new home is likely to be liable to pay CIL, so the owner should expect a Community Infrastructure Levy assessment as part of the planning process and deal with the forms before work starts. The London Plan space standards table also treats conversions as new dwellings, so each flat is measured like a new build, with no allowance for being in an old house. We price from the approved drawings and do not start on site until the consent and its pre-commencement conditions are cleared.

Housing in Bexley

By the valuation list's count, Bexley holds about 101,760 homes, 73% houses and 27% flats; by age, 11% were built before 1919, 41% between the wars and 48% since 1945. 36% of homes here are semi-detached; the side of a semi in Bexley is where a separate entrance for the upper flat is most often placed.

What Bexley expects from a house split into flats

Bexley expects a house to flats conversion to keep the outward appearance of the original single dwelling, without adding entrances. That usually means the flats share the existing front door and hall, with the separation done inside. New doors off the hall are not visible from the road, and bins, meters and bells are grouped so the front still reads as one house. Parking and cycle storage are best kept to the side or rear rather than spread across the whole front garden, which protects the streetscape the policy is concerned with.

Each new flat in Bexley is assessed against the space standards in D 22 of the Design Guide SPD Part 1, and every unit in a conversion needs external amenity space. On a semi or terrace that normally means dividing the rear garden, or giving the upper flat a terrace or garden strip of its own. The layout should also avoid putting living rooms and kitchens next to bedrooms in the neighbouring flat, above, below or alongside.

Sound and fire separation between Bexley flats

Bexley requires walls and floors between converted dwellings to meet at least Building Regulations Part E for impact, airborne and flanking sound. Approved Document E sets the performance for flats formed by a material change of use at 43 dB airborne for walls and floors, and 64 dB maximum impact for floors and stairs. The existing timber floors of an interwar house fall well short of that on their own.

Meeting it in a Bexley conversion usually means a new independent ceiling below the joists, acoustic insulation in the void, and a resilient layer and new deck above. Separating walls between flats need lining where the existing wall is thin, and the flanking paths round the edges of the floor have to be sealed. The floor and ceiling build-up also has to give the fire resistance Part B requires between flats, and the common stair becomes a protected escape route with fire doors to each flat.

Services, drainage and sign-off for a Bexley conversion

Each new flat needs its own services and its own identity. That means a separate electricity supply and meter, a separate gas supply or an all-electric heating system, and its own water supply or a sub-meter as the supplier allows, all planned before the walls are closed. New flats also need addresses through the council's street naming and numbering process. Where the scheme includes an extension or new structure near the drains, note that in Bexley a building notice cannot be used for construction within 3m of a drain or sewer controlled by Thames Water.

A conversion is a material change of use, and the shared hall and stair fall under fire safety law once the flats are occupied, so it goes in as a full plans application. Bexley formally checks full plans and issues a decision within five to eight weeks, and the application generally needs a construction specification and, where applicable, structural calculations for steel beams. Part L covers the new heating and any renewed walls, roof or windows, and Part K any new stair. Cutting into or building on a party wall brings in the Party Wall Act, and the building owner serves the notices on the neighbours. At the end, the notice of completion must reach Bexley not more than five days after the work is finished, and the completion certificate goes to the buyers' solicitors.

• Decoration, flooring and making good throughout, ready to let or sell
• Pre-completion sound testing arranged before sign-off
• A kitchen and shower room fitted in every new flat

VOA Council Tax stock of properties, March 2025, for all 28 statistical areas in Bexley. Counts rounded by the VOA.

Related reading for Bexley homeowners planning flat conversions: structural alterations in Bexley, our Bexley area guide, a building contractor for the whole conversion, party walls in a flat conversion, how we handle flat conversions across London and Renovation Budget & Contingency.

The GS Renovation Difference in Bexley

A conversion packs structural, fire, acoustic and services work into one building, and the sequence matters more than on almost any other job. We build to the planning consent and the Building Regulations drawings, run separate services to each flat's own meter position, and carry out the sound and fire separation before any finishes go on. The owner, their agent or designer applies for planning permission. We give you the programme and a record of what was built, and arrange access for the sound test before completion.

• Full plans application to building control, never a building notice
• Every flat checked against the space standard before the layout is priced
• Free, no-obligation quotations

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.