Flat Conversions Putney

A flat conversion in Putney is a planning question before it is a building one. Wandsworth's Local Plan, adopted on 19 July 2023, protects the existing self-contained housing stock and limits the conversion of single dwellings into flats through policies LP25 and LP26. With houses only 25% of Putney's homes, the period houses large enough to split are exactly the family homes those policies aim to keep. We build conversions once permission is granted, to the approved drawings.

In Putney, 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 Putney: 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.

Wandsworth conversion policy and the Putney family house

Splitting a Putney house into flats always needs planning permission, and the policy starting point is protection of family housing. Wandsworth's Local Plan limits the conversion of single dwellings into flats through policies LP25 and LP26, and the owner's architect or planning consultant has to show the scheme meets those tests. The drawings that come back approved are the ones we price and build. Until then any figure for the building work is a guide, because the number of flats and the stair position change the cost drivers.

A scheme that adds homes also meets the affordable housing policy. Under Wandsworth Policy LP23, developments of 1 to 9 dwellings (gross) must make a contribution per unit towards affordable housing, subject to indexation, unless at least 15% of the units are affordable on site. That sum belongs in the owner's appraisal alongside the build cost. In a Putney terrace a scheme only makes sense where the house is big enough to give good flats rather than squeezed ones.

Housing in Putney

Putney has about 20,990 homes on the Council Tax list: 36% pre-1919, 8% interwar and 54% post-war, with flats making up 75% and houses 25%. Most homes here are flats, and changing the number of flats in Putney needs the freeholder and usually planning.

Space standards for each new flat in Putney

Every new flat formed in a Putney conversion is a new dwelling under the London Plan, which counts conversions and change of use alongside new build. London Plan Policy D6 sets minimum space standards for all self-contained homes, so a one-bedspace single bedroom must be at least 7.5 square metres and 2.15m wide, and a two-bedspace double room at least 11.5 square metres. In a Putney terrace those sizes decide how many bedrooms each floor can hold, and a back addition bedroom can fail the width test first.

Ceiling height is where older Putney houses get tight. Policy D6 asks for a floor to ceiling height of at least 2.5m over at least 75 per cent of each dwelling's internal area. Tall Edwardian ground and first floors usually comply, but a top floor under the roof or a lower ground floor often does not, and a new acoustic ceiling takes height away. Wandsworth also applies its own housing standards in Local Plan policy LP27, including private internal space and daylight, so we measure every storey at the survey.

Fire separation and sound between flats in a Putney conversion

The hard building work in a Putney conversion is turning timber floors and stud walls into proper separations between homes. Under Part B each flat needs fire separation from its neighbours and a protected escape route, which usually means upgraded floors, fire doors to each flat, a protected stair and linked smoke detection. Building control checks these at each stage, and we leave floors and ceilings open for inspection before the boards and plaster close them up.

Sound matters as much as fire. Approved Document E sets the performance for flats formed by material change of use at 43 dB airborne for walls, floors and stairs, and 64 dB maximum impact for floors and stairs. In an old Putney house that normally means an independent ceiling, mineral wool, resilient bars and a floating floor above, with flanking paths around chimney breasts and skirtings sealed. We book the pre-completion sound test so the results arrive before handover.

Services, party walls and addresses for new Putney flats

Each new Putney flat needs its own supplies, meters and address, and these take longer than the building work if left late. We plan separate electricity and gas meters, a water supply for each flat where the supplier requires it, and soil stacks that line up floor to floor. Street naming and numbering for the new flats is applied for through the council, so the utilities can register each supply. A registered electrician certifies each flat's installation separately.

Where the conversion cuts into a party wall, for a new beam bearing or a flue, the Party Wall Act applies. Wandsworth's party walls page states that these matters are between adjoining owners and points owners to the government's explanatory booklet. As the building owner you serve the notices, often through a party wall surveyor, and we build to the neighbour's written consent or the award. In a Putney terrace that usually means both neighbours, so start notices early in the programme.

• Fire detection in every flat and the common hall, laid out to the fire strategy
• Fire stopping round every pipe and cable through a separating floor
• House to flat conversions into two or more self-contained units

VOA Council Tax stock of properties, March 2025, for Putney Embankment & Lower Common, Putney Town & Wandsworth Park, Putney West and East Putney. Counts rounded by the VOA.

Alongside flat conversions in Putney, the pages that usually help next are structural alterations in Putney, flat conversions across Wandsworth, building control sign-off for a conversion, refurbishing a flat that has already been converted, how we handle flat conversions across London and Party Wall Act Explained.

Why Putney Homeowners Choose GS Renovation

We build conversions to the approved drawings and the building control plans, with fire separation, sound insulation and services planned together rather than patched in later. The owner or their designer secures the planning permission, and we give them the method statements, programme and sound test results they need. A structural engineer designs the new openings and floor strengthening, a registered electrician certifies each flat, and nothing is closed up before building control has inspected it.

• Free, no-obligation quotations
• Each flat numbered and supplied before the keys are handed over
• Mains-wired, interlinked smoke and heat alarms to the approved fire strategy

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.