Typical planning ranges in London
What the London factor means
Our broad 1.28× regional model sits 28% above the national planning baseline. It is a UK Home Costs planning assumption rather than an externally measured city-wide price index. For projects with a large nationally priced equipment or materials component — such as solar, windows, EV chargers, insulation, underfloor heating and consumer units — the table uses only the documented share of that broad regional difference used by the corresponding calculator.
Planning considerations in London
- Allow separately for parking, loading, permits or restricted delivery windows where a property has difficult street access.
- Flats and managed buildings can add landlord, freeholder or building-management requirements that are outside a basic works estimate.
- Party-wall, structural and access costs should be checked independently on extensions, lofts and major internal alterations.
How to use these figures
Dense access, parking, deliveries and contractor overheads can widen the spread between quotations, so use the figures as an early budget rather than a quote.
Start with the table to understand project scale, then use a calculator to add floor area, condition, finish level and other project-specific inputs. A postcode-aware calculator can infer the same broad region while still allowing a manual override.
Compare this region with all locations
Detailed project cost guides in London
These pages apply the same transparent regional model — or the calculator's documented moderated regional treatment where appropriate — to detailed project tables rather than publishing a single city-wide headline figure.
Extension cost
Modelled London extension cost using the current £1,800–£3,000 per m² national benchmark before VAT and the UK Home Costs London regional planning model.
£1,800–£3,000 per m² national benchmark before VATOpen London guide →2026 regional guideLoft conversion cost
Modelled London loft conversion cost using the current £22,500–£80,000 across common 2026 conversion types and the UK Home Costs London regional planning model.
£22,500–£80,000 across common 2026 conversion typesOpen London guide →2026 regional guideRoof replacement cost
Modelled London roof replacement cost using the current £4,000–£19,000 for most roof replacements; £8,000 UK average and the UK Home Costs London regional planning model.
£4,000–£19,000 for most roof replacements; £8,000 UK averageOpen London guide →2026 regional guideHouse rewire cost
Modelled London house rewire cost using the current £3,000–£12,500 across common flats and houses and the UK Home Costs London regional planning model.
£3,000–£12,500 across common flats and housesOpen London guide →2026 regional guideNew boiler cost
Modelled London new boiler cost using the current £2,500–£4,000 like-for-like combi; £3,000–£15,000 broader installed projects and the UK Home Costs London regional planning model.
£2,500–£4,000 like-for-like combi; £3,000–£15,000 broader installed projectsOpen London guide →2026 regional guideSolar panel cost
Modelled London solar panel cost using the current £6,000–£10,000 for 3–6 kW solar-only systems; about £8,000 for 4 kW and the UK Home Costs London regional planning model.
£6,000–£10,000 for 3–6 kW solar-only systems; about £8,000 for 4 kWOpen London guide →2026 regional guideKitchen renovation cost
Modelled London kitchen renovation cost using the current £5,250–£28,400 current fitted-kitchen range; £10,550 UK average and the UK Home Costs London regional planning model.
£5,250–£28,400 current fitted-kitchen range; £10,550 UK averageOpen London guide →2026 regional guideBathroom renovation cost
Modelled London bathroom renovation cost using the current £5,500–£8,000 typical new bathroom; £7,000 UK average; £14,000+ high-end and the UK Home Costs London regional planning model.
£5,500–£8,000 typical new bathroom; £7,000 UK average; £14,000+ high-endOpen London guide →2026 regional guideWindow replacement cost
Modelled London window replacement cost using the current £500–£5,000+ per double-glazed window by type; £8,000–£15,000 for a typical 3-bed house and the UK Home Costs London regional planning model.
£500–£5,000+ per double-glazed window by type; £8,000–£15,000 for a typical 3-bed houseOpen London guide →2026 regional guideHome insulation cost
Modelled London home insulation cost using the current £654–£1,206 for common loft-quilt examples; £950–£4,600 cavity-wall examples by property type and the UK Home Costs London regional planning model.
£654–£1,206 for common loft-quilt examples; £950–£4,600 cavity-wall examples by property typeOpen London guide →2026 regional guideEV charger cost
Modelled London ev charger cost using the current about £1,000 typical home installation; eligible 2026 OZEV grants cover 75% up to £500 per socket and the UK Home Costs London regional planning model.
about £1,000 typical home installation; eligible 2026 OZEV grants cover 75% up to £500 per socketOpen London guide →2026 regional guideExternal wall insulation cost
Modelled London external wall insulation cost using the current £150–£200 per m² installed; £6,000–£30,000+ across common property examples and the UK Home Costs London regional planning model.
£150–£200 per m² installed; £6,000–£30,000+ across common property examplesOpen London guide →2026 regional guideUnderfloor heating cost
Modelled London underfloor heating cost using the current £50–£110 per m² across electric and wet new-build or renovation systems; £3,000–£13,000 for many full-property installs and the UK Home Costs London regional planning model.
£50–£110 per m² across electric and wet new-build or renovation systems; £3,000–£13,000 for many full-property installsOpen London guide →2026 regional guideConsumer unit cost
Modelled London consumer unit cost using the current about £485 for a typical installed 10-way RCBO unit; roughly £350–£800 by circuits and property size and the UK Home Costs London regional planning model.
about £485 for a typical installed 10-way RCBO unit; roughly £350–£800 by circuits and property sizeOpen London guide →Popular calculators
House renovation
Refine the London planning range with project-specific inputs.
Open calculator →Live calculatorHouse extension
Refine the London planning range with project-specific inputs.
Open calculator →Live calculatorLoft conversion
Refine the London planning range with project-specific inputs.
Open calculator →Live calculatorGarage conversion
Refine the London planning range with project-specific inputs.
Open calculator →Live calculatorKitchen renovation
Refine the London planning range with project-specific inputs.
Open calculator →Live calculatorBathroom renovation
Refine the London planning range with project-specific inputs.
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