Flat roof cost UK 2026
The going rate for flat roof in 2026 is 3-layer felt: £50–£80/m² · EPDM: £60–£90/m² · GRP: £70–£100/m² (supply & fit, ex scaffold). Below: a calculator, what the job involves, materials at three price levels, and the prep that changes the price.
Flat roof calculator
Market bands
| Option | Band | Source |
|---|---|---|
| 3-layer felt | £50–£80/m² | Trade2Base |
| EPDM | £60–£90/m² | Trade2Base |
| GRP | £70–£100/m² | Trade2Base |
What the job involves
| Stage | Task | Typical time |
|---|---|---|
| strip | Strip old covering | 0.3 h per m² |
| strip | Check and prep deck | 0.1 h per m² |
| system | Lay flat roof system | 0.6 h per m² |
| system | Edge trims and upstands | 0.3 h per m² |
Materials at three price levels
| Material | Budget | Trade choice | Premium |
|---|---|---|---|
| Flat roof edge trims per m | £6 Standard trims — Finishes the edge | £9 System-matched trims — Warranty-backed detail | £14 Aluminium edge system — Crisp, durable edge |
Trade prices ex VAT, estimates checked 2026-09-25. Log your receipts in Grafto and your own prices replace these.
What changes the price
- System? 3-layer felt · EPDM · GRP big effect
- Deck condition? sound · soft spots · unknown big effect
- Insulation? keep cold deck · upgrade to warm deck
- Edge trim length (m)?
- Storeys? 1 · 2 · 3 big effect
- Property built? 2000 or later · before 2000 · unknown
Good practice
- Torch-on needs dry weather: one weather day allowed in the diary
- GRP is temperature-limited: one weather day allowed in the diary
- Warm deck: insulation above the deck, the preferred build
Prep to look for
| Condition | Check | Effect |
|---|---|---|
| Flat roof defects | ponding water, blisters, splits in the covering | Ponding: check falls (at least 1:80) when re-covering |
| Rotten deck | Any soft spots when you walk the deck? | Deck replacement where rotten, only if found £300–£1,200 |
| Possible asbestos cement | corrugated or flat fibre-cement sheets, old soffits | Possible asbestos cement: test before disturbing |
| Rotten fascia or sagging gutters | sagging gutters, rotten or flaking fascia boards | Fascias and gutters need replacing: quote the roofline while scaffold is up |
Questions
How much does flat roof cost in the UK in 2026?
The researched market band is 3-layer felt: £50–£80/m² · EPDM: £60–£90/m² · GRP: £70–£100/m² (supply & fit, ex scaffold), from Trade2Base. A worked example of 20 m² comes to about £1,592–£2,147 across budget, trade and premium materials.
How long does flat roof take?
The worked example of 20 m² takes about 1.5 working days.
What changes the price of flat roof?
Mainly system, deck condition, storeys, plus any prep found on site: flat roof defects, rotten deck, possible asbestos cement, rotten fascia or sagging gutters.