Ask any London homeowner who’s just finished a home renovation what surprised them most, and the answer is rarely the finish, the colour, or even the builder. It’s the bill. Not because it was necessarily unfair — but because nobody told them what “normal” actually looks like before they started.
If you’re weighing up a new kitchen, a loft conversion, or a full top-to-bottom refurbishment this year, here’s the honest, unglamorous version of what it costs to renovate in London in 2026 — and where the money quietly disappears.
The headline number
Renovation costs are usually quoted per square metre, and in London that figure sits noticeably above the rest of the country. As a rough guide for 2026:
- Light refresh (decorating, flooring, updated fixtures): roughly £800–£1,200/m²
- Mid-range renovation (new kitchen and bathroom, rewiring, replastering, quality finishes): roughly £1,200–£1,800/m²
- High-end renovation (structural changes, bespoke joinery, premium materials): £1,800–£2,500/m²+
- Heritage or listed-building work: £2,500–£3,500/m²+
For a typical three-bedroom London home of around 100–120m², that translates to somewhere between £100,000 and £200,000 for a proper mid-range renovation — and yes, that’s before anyone’s touched an extension.
London simply costs more than the rest of the UK, usually by 25–40%. Blame it on labour demand, parking and scaffold permits, tighter borough planning rules, and the sheer number of Victorian and Edwardian properties hiding surprises behind their walls.
What each room actually costs
Averages are useful, but most people budget room by room. Here’s roughly where the money goes:
- Kitchen: £12,000 for a straightforward refit, up to £30,000–£40,000+ for bespoke cabinetry and premium appliances
- Bathroom: from around £4,000–£8,000 for a like-for-like update, to £18,000+ for a full reconfiguration with natural stone and underfloor heating
- Loft conversion: £25,000 for a simple Velux conversion, up to £70,000–£120,000 for a full mansard with en suite
- Rear extension: typically £2,000–£3,500/m² in London, so a modest 20m² extension can land anywhere from £40,000 to £90,000
- Interior decorating alone (painting, wallpaper, flooring, no structural work): often £4,000–£10,000 depending on the size of the property and quality of finish
Kitchens and bathrooms consistently swallow 30–40% of a whole-house renovation budget, so if you’re planning to phase your project, that’s usually where the priority — and the return on investment — lies.
The hidden costs nobody budgets for
This is where most renovation budgets quietly fall apart:
- Contingency: set aside 10–15% of your total budget for the unexpected. On period properties especially, this isn’t optional.
- Party wall agreements: if you’re extending near a neighbouring property, factor in legal and surveyor fees.
- Skip hire, parking permits, scaffold licences: small individually, but they add up fast in central boroughs.
- Structural surprises: damp, old wiring, and timber issues are common in properties that haven’t been touched in 20+ years, and they rarely show up until walls are opened.
A detailed, itemised quote before work starts is the single best way to avoid these becoming budget-breaking surprises later.
How to keep costs under control
A few things consistently separate renovations that stay on budget from ones that don’t:
- Get a proper survey before you price anything. Assumptions about wiring, damp, or structural conditions are where budgets go wrong.
- Fix your spec before work begins. Changing your mind about tiles or layout mid-project is one of the most common causes of cost overruns.
- Work with tradespeople who know London properties specifically. A contractor used to modern new-builds can be caught out by a Victorian terrace’s quirks — and that shows up in your final invoice.
- Get more than one quote, and read what’s excluded, not just what’s included.
This last point matters more than people expect. London-based renovation specialists such as Nemo Group UK, who’ve spent over a decade working across Greater London’s mix of period and modern properties, generally start with an on-site assessment precisely so hidden issues are flagged before a number is put on paper — rather than added as a surprise once the job is underway.
Is it worth it?
Despite the numbers above, renovation remains one of the more reliable ways to add real value to a London property — a well-executed kitchen or bathroom renovation alone can add several per cent to a home’s resale value, on top of simply making it a nicer place to live.
The real risk isn’t the size of the budget. It’s going in without one. Get a proper quote, build in a contingency, and choose a contractor who’s renovated London homes before — not just houses in general.
Do you have a renovation project in mind? Nemo Group UK offers renovation, painting and decorating, and full home improvement services across London — get in touch for a tailored quote.
