Flat Conversions Pimlico

Few houses in Pimlico are left to split: 94% of homes here are already flats, and the 6% that are houses are terraced. So flat conversion work in Pimlico can mean reworking an older conversion inside a stucco townhouse or joining flats back into one home, as well as dividing a house for the first time. Dividing a house always needs planning permission, and the new flats are tested against London's space standards and the building regulations for separation between flats.

In Pimlico, 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 Pimlico: 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 a house into flats in Pimlico

Turning a Pimlico house into flats needs planning permission, because it is a material change of use that creates new dwellings. The application is judged against Westminster's City Plan, whose current version was adopted on 21 January 2026 after a Partial Review, and against the Pimlico Neighbourhood Plan, adopted on 7 December 2022. Your designer reads both before fixing the number and mix of flats, and in particular any policy on keeping family sized homes.

Two further planning points follow from new homes. Westminster charges CIL per square metre on new dwellings of any size, so the levy is part of the budget from the first sketch. The London Plan also counts residential conversions among the forms of small site intensification where they add housing. Where the house is in the Pimlico Conservation Area, external changes such as new entrances or meter boxes on the front are drawn with the council's conservation rules in mind.

Housing in Pimlico

Pimlico has around 10,180 homes on the Council Tax list: 34% post-war, 10% interwar and 55% predate 1919, with 94% flats and 6% houses. Since most homes here are flats, a flat in Pimlico can be split or combined only with the freeholder's consent, and changing the number of homes usually needs planning permission as well.

Space standards for new flats formed in Pimlico

New flats carved out of a Pimlico house must meet the London Plan's minimum sizes. Policy D6 applies its space standards to every tenure, and counts conversions and changes of use as new dwellings. A single bedroom needs 7.5 square metres and 2.15m of width, and a double or twin 11.5 square metres. Narrow rear rooms can fail the width test first, so the stair position drives the plan. Your designer tests each proposed flat before the layout is fixed.

Height is tested as well. D6 wants 2.5m from floor to ceiling across at least 75 per cent of the internal area of each new flat. The main floors of a stucco townhouse tend to clear that, while a top floor under the roof slope or a low lower ground floor may fall short. D6 also asks for dual aspect flats where possible and, where Westminster sets no higher standard, private outdoor space of at least 5 square metres for a one or two person flat. Your designer measures each level of the Pimlico house first.

Fire and sound separation between flats in a Pimlico conversion

Separation under Part B is the heart of the building work in any Pimlico conversion. Each new flat becomes its own fire compartment, so the floors and walls between flats are upgraded to the fire resistance the approved design sets and building control agrees. In a stucco townhouse that usually means new fire-rated ceilings under the old joists, fire-resisting doors onto a protected stair, and linked detection in the common parts. Every pipe and cable that passes through a separating floor is fire stopped before the ceiling is closed, because a gap there defeats the whole compartment.

Sound is the other half, because each flat sits on top of another. Approved Document E asks converted flats to reach 43 dB airborne sound insulation through separating walls and floors and no more than 64 dB impact sound through floors. In a timber floored Pimlico townhouse that usually means a new ceiling on resilient bars, insulation between joists and an upgraded floor. Pre-completion sound tests are booked before decoration, while any remedial work is still easy to do.

Services, addresses and party walls for Pimlico flats

Each new flat in a Pimlico conversion needs its own services, so the utility work starts early. That means separate electricity and gas meters where gas is kept, a water supply and drainage for each kitchen and bathroom, and new postal addresses through the council's street naming and numbering. Meter positions in a stucco front are awkward, so they are often placed in the lower ground floor or the entrance hall.

A registered electrician installs and certifies each new supply, and Westminster's policy is to issue the completion certificate only once all fees are paid and all electrical and gas certificates are supplied. Where a party wall is cut into for new steels or fire stopping, the Party Wall Act applies, and the building owner serves the notices on the neighbours. New openings are built to a structural engineer's design, and the party wall work goes ahead on the neighbour's written consent or under an award.

• Common hallway, stair and entrance finishes
• Splitting a large flat in two, or joining two flats into one
• Steel beams and new openings built to the engineer's design

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

Work in Pimlico rarely sits on its own, so you may also want structural alterations in Pimlico, flat conversions across Westminster, building control sign-off for a conversion, the Party Wall Act when a conversion cuts a shared wall, how we handle flat conversions across London and Who Pays the Party Wall Surveyor.

Trusted Flat Conversions in Pimlico

We build conversions as one managed job, from strip out and structural work to the fire and sound separation and the finished flats, so the owner has one team answering for the sequence. Your designer or agent handles planning, and we build to the consent and supply the programme and construction details they need. New openings or stairs are built to a structural engineer's design, and a registered electrician certifies the new supplies for each flat.

• Common parts, bin stores and cycle stores finished to the planning conditions
• Aftercare and snagging support once the job is finished
• Full plans application to building control, never a building notice

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.