Renovating a London flat comes with its own budget shape and its own constraints. A mid-range full renovation typically costs around £55,000 for a one-bedroom flat and around £85,000 for a two-bedroom flat, with premium specifications in boroughs such as Kensington and Chelsea or Westminster running £2,500 to £3,500 per square metre. This guide covers realistic 2026 cost bands and the leasehold factors that can affect both budget and programme.
Flat renovation cost in London by size and specification
A mid-range full renovation, covering a new kitchen, a new bathroom, rewiring, replastering where needed and full redecoration, typically costs around £55,000 for a one-bedroom flat of roughly 45 to 55 square metres, and around £85,000 for a two-bedroom flat of roughly 65 to 80 square metres. These figures assume the existing layout is largely retained, with the kitchen and bathroom staying in their current positions.
Per-square-metre bands mirror the ranges for London houses, with one adjustment at the top end. A light refresh runs £800 to £1,200 per square metre, a mid-range renovation £1,200 to £1,800 per square metre, and a premium renovation £2,000 to £3,500 per square metre, with the upper end of that premium band reflecting the high-specification finishes common in Kensington and Chelsea, Westminster and similar prime central London postcodes.
London flat renovation cost guide (2026)
Item
Typical range
Notes
One-bedroom flat, mid-range full renovation
~£55,000
New kitchen, bathroom, rewire, replaster, redecoration
Two-bedroom flat, mid-range full renovation
~£85,000
New kitchen, bathroom, rewire, replaster, redecoration
Premium renovation, prime central London spec
£2,500–£3,500/sqm
Kensington & Chelsea / Westminster-tier finish
Light refresh (any size)
£800–£1,200/sqm
Redecoration, flooring, minor repairs only
Figures are a typical London market guide, not a fixed Lian Construction quote. Flat layout, existing condition and building access all affect the final price.
Leaseholder and freeholder considerations before you renovate
Most London flats are leasehold, which means renovation work usually needs a licence to alter from the freeholder or managing agent before it starts, even for internal work that does not touch the building structure. This is standard UK leasehold practice rather than anything specific to one building, and it typically covers work such as removing internal walls, changing flooring type, or altering the layout of a bathroom or kitchen.
It is worth checking the lease early, since some leases require flooring to include a minimum level of sound insulation, particularly in converted period buildings and purpose-built blocks with residents below. Applying for a licence to alter in parallel with getting quotes, rather than after, keeps the renovation programme moving instead of stalling once the contractor is ready to start.
Noise and access constraints in blocks and converted buildings
Working hours are usually restricted in managed blocks, often to weekdays and Saturday mornings, with no noisy work permitted on Sundays or bank holidays. Some buildings also limit the number of weeks of building work permitted per lease year, which is worth checking against your renovation timeline before committing to a schedule.
Access is a practical constraint too. Lifts, stairwells and shared corridors need protecting, skips or waste bags may need to be carried down rather than dropped from a window, and parking for a builder's van in central London postcodes can require a resident or contractor permit. None of this changes the scope of the renovation, but it does affect programme and should be priced into the project from the outset rather than discovered mid-job.
Worked examples for common London flat types
A one-bedroom converted-Victorian flat of around 50 square metres, renovated to mid-range specification with a new kitchen, new bathroom, rewire and full redecoration, typically lands close to the £55,000 benchmark, assuming the existing layout is kept and there is reasonable access for materials and waste.
A two-bedroom purpose-built flat of around 75 square metres in a mansion block, renovated to the same mid-range specification, typically lands close to the £85,000 benchmark. Moving to a premium specification in a prime central London postcode, with high-end kitchen and bathroom fittings, engineered flooring throughout and bespoke joinery, can push either flat type toward the £2,500 to £3,500 per square metre band, which for a 75 sqm two-bedroom flat means a total closer to £190,000 to £260,000.
What affects flat renovation cost most
Where flat renovation costs increase
Relocating a kitchen or bathroom to a different position in the flat is the biggest single driver, since it usually means new drainage runs, often through a solid floor rather than a suspended one. Poor existing condition behind original plaster or under old flooring, restricted lift or stair access in a period conversion, and building-specific requirements such as enhanced sound insulation between flats all add cost.
Where flat renovation costs stay lower
Keeping the kitchen and bathroom in their existing positions, working within the freeholder's standard licence to alter conditions rather than requesting exceptions, and specifying mid-range rather than bespoke joinery and fittings all help keep a flat renovation closer to the lower end of its cost band. Our property refurbishment London team can advise on which of these choices matter most for a specific flat during survey.
Planning and building regulations for flat renovation
As with houses, most internal flat renovation work does not need planning permission, since it does not change the external appearance of the building. Building regulations apply to structural changes, such as altering a wall between rooms, and to a full rewire or new bathroom installation, which needs to meet current electrical safety requirements. Where a flat sits within a converted period building, party structure rules can also apply to work on a wall shared with a neighbouring flat, in addition to the leaseholder consent already covered above.
If the renovation follows leak damage or an existing building defect, our leak repairs London team can assess the affected ceilings, walls and finishes as part of the same renovation scope, rather than treating repair and renovation as two separate projects.
Questions
Frequently asked questions
How much does it cost to renovate a one-bedroom flat in London?
A mid-range full renovation of a one-bedroom flat in London, including a new kitchen, new bathroom, rewire and redecoration, typically costs around £55,000, assuming the existing layout is kept.
How much does it cost to renovate a two-bedroom flat in London?
A mid-range full renovation of a two-bedroom flat typically costs around £85,000, rising toward £2,500 to £3,500 per square metre for a premium specification in a prime central London postcode.
Do I need permission from my freeholder to renovate my flat?
Most leasehold flats require a licence to alter from the freeholder or managing agent before renovation work starts, even for internal-only work. It is worth checking your specific lease and applying early, in parallel with getting quotes.
Are there restrictions on when building work can take place in a block of flats?
Yes. Managed blocks typically restrict noisy work to weekdays and Saturday mornings, with some buildings also capping the number of weeks of building work allowed per lease year.
Does flat renovation cost more than house refurbishment per square metre?
The per-square-metre bands are broadly similar to houses at the light and mid-range tiers. At the premium end, prime central London flats can run higher, up to £3,500 per square metre, reflecting the finish specification common in those buildings.
What is the biggest cost driver in a flat renovation?
Relocating a kitchen or bathroom to a new position in the flat is usually the single biggest driver, since it typically requires new drainage routes through the floor structure.
Can Lian Construction help with the licence to alter process?
We can provide the drawings and specification a freeholder or managing agent typically asks for as part of a licence to alter application, and sequence the renovation programme around approval timescales.
Get a free, no-obligation quote from Lian Construction
Send the site address, photos if available, and a short description of the work. Lian Construction surveys London properties in Kingston upon Thames and across all boroughs, then provides a clear written quote before any work starts.