Roof replacement cost calculator
Roofing is priced per square metre, plus scaffold, plus everything you should do while the scaffold is up. Set it out here before you get quotes.
Last updated July 2026 · built by working UK builders
A roof "at the end of its life" in a survey rarely means water is coming in tomorrow. Concrete tiles last 40–60 years, natural slate 80–100+. Ask what is actually failing.
Replacing more than 25% of a roof covering triggers building regulations — the insulation usually has to be upgraded too.
The rates behind this calculator
All figures are 2026 UK prices for a competent, insured, VAT-registered contractor. Costs are shown as ranges because building work is delivered in ranges. A “×” value multiplies the whole build cost.
What is the job?
| Option | Cost | Effect on total |
|---|---|---|
| Localised repair Slipped tiles, a few slates, small area of felt | £350–£1,400 | Added |
| Strip and re-cover (pitched) New membrane, battens and covering — £90–£170 per m² | £90–£170 per m² | Added |
| Flat roof — torch-on felt £90–£150 per m² | £90–£150 per m² | Added |
| Flat roof — EPDM rubber £100–£170 per m² | £100–£170 per m² | Added |
| Flat roof — GRP fibreglass £110–£190 per m² | £110–£190 per m² | Added |
| Flat roof — single ply or zinc £160–£300 per m² | £160–£300 per m² | Added |
Covering material
Only applies to a pitched re-cover.
| Option | Cost | Effect on total |
|---|---|---|
| Concrete interlocking tiles | — | ×1 |
| Clay plain tiles | — | ×1.35 |
| Fibre cement slate | — | ×1.1 |
| Natural slate (Welsh or Spanish) | — | ×1.55 |
| Reclaimed / heritage to match | — | ×1.7 |
What else needs doing while the scaffold is up?
Scaffold is the expensive bit. Do everything at height in one visit.
| Option | Cost | Effect on total |
|---|---|---|
| Scaffold Two-storey semi, typically 2–4 weeks on hire | £900–£3,000 | Added |
| New fascias, soffits and guttering | £1,200–£4,000 | Added |
| Chimney repointing and new flashings | £900–£3,500 | Added |
| Chimney stack rebuild | £2,200–£6,000 | Added |
| Replacing rotten rafters, purlins or wall plate | £1,500–£8,000 | Added |
| Loft insulation topped up to 270mm | £400–£1,400 | Added |
| Insulating at rafter level (warm roof) | £60–£130 per m² | Added |
| New rooflights | £900–£3,000 | Added |
| Valley or lead work renewal | £700–£3,000 | Added |
| Asbestos cement sheet removal | £800–£4,000 | Added |
Where is the property?
Labour rates and builder demand vary more than materials do.
| Option | Cost | Effect on total |
|---|---|---|
| London | — | ×1.25 |
| South East | — | ×1.12 |
| South West | — | ×1.03 |
| East of England | — | ×1.03 |
| Midlands | — | ×0.97 |
| North of England | — | ×0.92 |
| Wales | — | ×0.92 |
| Scotland | — | ×0.95 |
| Northern Ireland | — | ×0.85 |
Applied to every total
| Item | Amount |
|---|---|
| Contingency | 10% of build cost |
| VAT | Included at 20% unless stated |
How long roof coverings actually last
| Covering | Typical life | Usual failure point |
|---|---|---|
| Concrete interlocking tiles | 40–60 years | Surface erosion, moss, ridge mortar |
| Clay plain tiles | 60–100 years | Frost damage, nail fatigue |
| Natural slate | 80–150 years | Nail sickness — slates slip while slates are fine |
| Fibre cement slate | 30–50 years | Delamination at the edges |
| Torch-on felt (flat) | 15–25 years | Blistering, splits at upstands |
| EPDM rubber (flat) | 20–30 years | Poor detailing at outlets and edges |
| GRP fibreglass (flat) | 20–25 years | Cracking at joints if laid in the cold |
| Single ply / zinc | 30–40 years | Fixings and movement joints |
| Bitumen underfelt (any pitched roof) | 25–40 years | Perishes and tears — the real reason for most re-roofs |
Repair or replace?
The honest test is not the age of the tiles but the condition of what is underneath. If the tiles are sound and the felt has perished, you are re-roofing whether you like it or not, because the felt cannot be replaced without stripping the covering. If the felt is intact and you have a dozen slipped slates, that is a day's work and a few hundred pounds.
Get into the loft on a bright day and look up. Daylight through the felt, torn valleys, staining down the rafters and damp wall plates tell you more than any number of photographs of the outside.
The things worth doing at the same time
- Chimney repointing and flashings — the single most common source of upstairs damp.
- Fascias, soffits and guttering — cheap while access exists, expensive alone.
- Dry-fix ridge and verge — mortar-bedded ridges are a maintenance item forever; dry-fix is not.
- Loft insulation to 270mm — trivial cost, immediate saving.
- Rooflights — far cheaper installed during a re-cover.
Roofing red flags
Be careful of anyone who knocks on the door offering to fix your roof, quotes without going up, recommends spray-on foam insulation to the underside of the tiles, or wants a large cash deposit for materials. Spray foam in particular causes real problems: several mortgage lenders will not lend on a property that has it, and removal is expensive.
A proper roofing quote states the covering, the underlay type, the batten spec, the fixing pattern, what happens to the ridges and verges, the scaffold period and who takes the waste away. If it fits on a postcard, it is not a quote.
Frequently asked questions
How much does a new roof cost in the UK in 2026?
Stripping and re-covering a pitched roof costs £90–£170 per m² for concrete tiles, rising to £250+ per m² for natural slate. On a typical 80m² semi-detached roof that is roughly £9,000–£16,000 for concrete tiles including scaffold, or £18,000–£25,000 in natural slate.
My survey says the roof covering is at the end of its life. Is it leaking?
Usually not. Surveyors describe expected remaining life, not current failure. Concrete tiles last 40–60 years, clay 60–100, natural slate 80–150. What actually fails first is the underfelt, the mortar bedding on ridges and hips, and the flashings. Ask what specifically is defective before you assume a full re-roof.
Do I need building regulations approval to replace a roof?
Yes, if you are replacing more than 25% of the roof covering. That triggers a requirement to upgrade insulation to current standards, which is usually done at rafter or ceiling level and adds cost. Localised repairs below 25% do not.
How long does a flat roof last?
Torch-on felt gives 15–25 years, EPDM rubber 20–30, GRP fibreglass 20–25 if installed in good conditions, and single-ply or zinc 30–40. Falls and detailing matter more than the material — a flat roof that ponds water will fail early whatever it is made of.
Why is scaffold such a big part of the cost?
Because it is a separate trade with its own erection, hire period, inspection and dismantling costs, and it stays up for the whole job. On a two-storey house expect £900–£3,000. This is exactly why you should do the chimney, the fascias, the gutters and any rooflights in the same visit.