What does a garage conversion cost in London?
In London: £15,000 to £27,500 at mid-range, including 20% VAT, against £12,000 to £22,000 nationally. Budget starts around £11,300, premium runs to £41,300. Set your finish level and region below, no email required.
What the sources say
Checkatrade, Garage Conversion Cost: £10,000 to £20,000
16 m2 integrated or attached garage, stated + VAT; integral £10,000-14,000. Prices stated excluding VAT. Guide dated 2026-05, opened and checked 2026-08-26.
MyJobQuote, Garage Conversion Cost: £8,000 to £45,000
average standard conversion £14,500; £450-1,700 per m2. The guide does not state its VAT treatment. Guide dated 2026-07, opened and checked 2026-08-26.
The national range at the top of this page is chosen inside the spread these guides publish, converted to include 20% VAT where a guide states its prices exclude it. Where guides disagree, both figures stay visible above so you can judge for yourself.
Garage conversion, mid-range, London
£15,000 to £27,500
Including 20% VAT. An indication, not a quote: prices vary per trade and property.
Take it further
Nothing here is saved unless you ask. With a free account you can keep this estimate and come back to it later.
Prices include 20% VAT. New builds and some energy-saving works can qualify for 0% or reduced VAT; ask your installer.
On top of whatever you agree with a builder, set aside a contingency of 15 to 20% for the unforeseen: this work opens up the existing fabric, where damp, rotten timber or outdated wiring only show once things are apart. How much contingency you need explains the guidance.
Extensions and loft conversions often fall under permitted development. Check before you budget.
What drives the price
- The floor: garage slabs sit lower and colder than house floors; raising and insulating it is core work.
- The door opening: replacing the garage door with an insulated wall and window.
- Heating and electrics: extending the central heating and circuits into the new room.
- Integral versus detached: an integral garage converts cheaper than a detached one.
All figures come from the same validated 2026 price data as the calculator above, built on the sources listed higher up on this page, each opened and checked on 26 August 2026 (see how we price), so this page and your estimate can never disagree. Outside London? See the national guide, or compare every region in the regional overview. How to pay for it (remortgage, loan or savings) is its own guide: paying for a renovation. Planning an extension or loft? Check permitted development first.
Frequently asked questions
Does a garage conversion add value?
Usually yes when it becomes a real habitable room with building regulations sign-off, and especially where bedrooms or home offices are scarce. An uninsulated conversion without sign-off does the opposite at survey time, so budget for doing it properly.
What should I do first?
Three steps, in this order. First, turn the guide range above into your own number: the calculator on this page adjusts for size, finish level and region in under a minute, free and without email. Second, if the layout matters, bathrooms and kitchens especially, draw the room to scale in the free planner; moving plumbing is usually the biggest hidden cost, and you want to know that before anyone quotes. Third, get at least three itemised quotes and compare them line by line against your range before you commit; the quote check on this site gives you an honest verdict per quote.
Do these prices include VAT?
Yes, all ranges include 20% VAT. New builds and some energy-saving works can qualify for 0% or reduced VAT; ask your installer whether your project applies.
Why is London so much more expensive?
Labour is the driver: London trades charge roughly 25% above the national average, and parking, access and waste logistics add friction. Nationally this project runs £12,000 to £22,000; the calculator switches region in one click.
How accurate is this range?
It is a guide range from national 2026 cost guides, adjusted for finish level and region. Real quotes vary per trade, property and specification; treat it as a starting point, budget 10 to 15 percent contingency, and always get at least three itemised quotes.