Flat Conversions Welling

Flat conversion in Welling means dividing a house into self-contained flats, or combining flats back into one house. In the VOA's Welling statistical area, one of several covering DA16, 78% of homes are houses and 58% are semi-detached or detached, so the building that comes forward is likely to be an interwar semi or a larger terrace. Planning permission is always needed to turn a house into flats. The owner or their designer secures it; we build the separation, services and finishes to it.

In Welling, 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 Welling: 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.

What Bexley looks for when a Welling house becomes flats

Split into flats, a Welling house still has to read as a single house from the pavement. Bexley expects a conversion to keep the outward appearance of the original single dwelling without adding entrances. Code B 12 of its Design Guide SPD Part 2 asks each conversion to achieve appropriate internal space standards and avoid unacceptable impacts on the streetscape or local amenity. Bexley also requires external amenity space for every unit.

In practice the upper flat is reached through the existing front door and a shared lobby, with a protected stair behind it, rather than a new door cut into the front of the semi. The rear garden is divided so each flat has outdoor space, with a path to the upper flat's share. Bins, meters and cycle storage need a place that does not clutter the front garden, and we set those out on the approved plan.

Housing in Welling

The Council Tax list puts the Welling statistical area at about 4,020 homes, 21% flats against 78% houses; 5% went up before 1919, 76% between the wars and 18% after 1945. Semi-detached houses make up 56% of homes here, and the side of a semi in Welling is where a separate entrance for the upper flat is most often placed.

Room sizes and space standards for Welling conversions

Each flat in a Welling conversion is measured against a space standard before a wall is built. Bexley assesses new homes created by conversion against the standards in D 22 of its Design Guide SPD Part 1, and the London Plan table treats conversions as new dwellings. Under London Plan Policy D6, a single bedroom must be at least 7.5 square metres and 2.15m wide, and a double at least 11.5 square metres.

Height is where an interwar house can fall short, in the roof space and under a low rear addition. Policy D6 sets a floor to ceiling height of 2.5m over at least 75 per cent of each flat's gross internal area. GOV.UK notes that the Nationally Described Space Standard sits in the planning system rather than the building regulations, so the sizes are fixed at drawing stage. We then set out the partitions to those dimensions and check them before plastering.

Sound and fire separation between flats in a Welling house

In a Welling conversion, the floor between the two flats does more work than any other part of the job. Bexley requires walls and floors between converted dwellings to meet at least Part E of the Building Regulations for impact, airborne and flanking sound. For flats formed by a material change of use, Approved Document E asks for 43 dB airborne insulation and allows no more than 64 dB impact sound through floors and stairs.

Bexley also asks that living rooms and kitchens are not placed beside or above a neighbour's bedroom, so the plan does part of the acoustic work. On site we build an independent ceiling and acoustic insulation into the old timber floor, and that build-up is specified to reach the fire resistance Part B requires between flats. The stair becomes a protected escape route with fire doors and linked alarms, and a pre-completion sound test proves the floor.

Services, addresses and neighbours in a Welling flat conversion

Each new Welling flat needs its own services: a separate electricity supply and meter, its own heating and hot water, and a water supply the utility can bill separately. The network operators need applications and lead time, so we request the new supplies as soon as consent is granted. The new flats also need addresses through Bexley's street naming and numbering service before the utilities will register them, which the owner arranges.

Bexley states that development creating a new home is likely to be liable to pay CIL, so the owner or their agent deals with the liability notice before work starts. Where steel bears on a party wall or the wall is cut into, the Party Wall Act applies: the building owner serves notice, and the work goes ahead on written consent or an award. The London Plan counts residential conversions as small site intensification where they add homes, which is the policy case a Welling conversion rests on.

• Heating and hot water for each flat, gas by a Gas Safe registered engineer
• Insulation to the walls, roof and floors the conversion touches
• Pre-completion sound testing arranged before sign-off

VOA Council Tax stock of properties, March 2025, for the Welling statistical area, one of several statistical areas covering DA16. Counts rounded by the VOA.

If you are weighing up options for your Welling property, it is worth reading structural alterations in Welling, flat conversions across Bexley, builders in London who take on conversions, the Party Wall Act when a conversion cuts a shared wall, our London flat conversions page and Getting Planning Permission.

The GS Renovation Difference in Welling

We build Welling flat conversions to the consent your designer secured, as one contractor for the strip out, separating floors, protected stair, new kitchens and bathrooms, and finishes. New openings are built to a structural engineer's design, the registered electrician we bring in certifies each flat's installation, and we book the sound test before decoration. You get a written price after a site visit, a written programme and a record of the separation works for building control and your lender.

• Founder with 30+ years of hands-on experience
• Full plans application to building control, never a building notice
• Separating floors built to the acoustic detail the sound test checks

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.