A flat roof replacement strips the old covering from a low-pitched roof and lays a new waterproof system, usually EPDM rubber, GRP fibreglass or torch-on felt, over a sound deck with correct falls, upstands, trims and outlets so rainwater drains away.
Cost is usually the first question about a new flat roof, so here is the guide for the East Midlands: £1,900–£4,300 including VAT. We cover the whole of Northamptonshire, with Northampton, Corby, Kettering and Wellingborough among the main centres. Because each UK nation sets its own rules, we check the requirements in England for your property, then put a firm price on paper following a free survey.
- Guide price
- £1,900–£4,300 inc VAT
- Time on site
- 1–3 days for most roofs
- Planning rules
- England
- Price level
- About 4% below the national guide
- Towns listed
- 7
- Survey
- Free, with a written quote
How much does a new flat roof cost in Northamptonshire?
What should you budget for a new flat roof in Northamptonshire? Use the figures below as a starting point. Prices in the East Midlands sit about 4% below the national guide, so the range here is £1,900–£4,300 including VAT. Your fixed price comes in writing once we've surveyed the property, at no charge.
| Type of job | What it usually involves | Guide in Northamptonshire |
|---|---|---|
| Small roof (up to 8m²) | A dormer, bay, porch or small garage roof re-covered in EPDM or GRP. | £750–£1,900 |
| Extension or garage (15–25m²) | A typical extension or single garage roof stripped and re-covered. | £1,900–£4,300 |
| Large or new warm roof | Larger roofs, or roofs needing a new deck and insulation build-up. | £3,800–£8,600 |
The main things that change the figure:
- Roof area and access to the roof
- Covering system: EPDM, GRP or torch-on felt
- Condition of the deck and joists underneath
- Insulation upgrades and changes to roof height at edges
What do you get?
- Survey of the covering, deck, falls, upstands and drainage
- Stripping and disposal of the old roof covering
- Insulation upgrade to a warm roof build-up where agreed
- New EPDM, GRP or torch-on felt membrane laid to falls
- Upstands, flashings and drip edges finished neatly
- New trims, outlets and gutter connections
Housing across Northamptonshire
Orange-brown ironstone is the signature material of many Northamptonshire villages, with limestone and Collyweston stone-slate roofs in the north-east. Northampton has Victorian terraces from its shoemaking era, Corby expanded as a post-war steel town, and Wellingborough, Kettering and Daventry have interwar, post-war and recent estates.
Ironstone cottages often need lime repairs and careful repointing. Terraces suit loft conversions and kitchen extensions, while estate homes commonly take garage conversions, porches and driveways.
An inland county with cold winters and clay soils that can shrink in dry spells; ironstone weathers and needs a suitable mortar.
Planning and building rules in Northamptonshire
Northamptonshire is in England, so the planning and building rules set out below are the ones that apply. We confirm the details with the council before we quote.
Re-roofing a house with similar materials does not usually need planning permission in England. Listed buildings and conservation areas may need consent if the covering changes.
Replacing more than a quarter of a roof’s covering counts as renovation under Building Regulations, so the work is notified and the roof insulation may need upgrading. Bats are protected across the UK; if they roost under roof tiles, soffits or fascias, work stops and a licensed ecologist advises before it restarts.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
How does the job run?
We look at the job
It starts with a survey at the property, free of charge. We check condition, access and services, ask how you want the finished result to look, and answer any questions you have about a new flat roof.
Written quote
You get the price in writing, itemised so you can see where the money goes. As long as the specification stays the same, that is the price you pay for a new flat roof.
Getting ready
Next comes planning the work itself. We set a start date that suits you, line up the right trades, and make sure any approvals for a new flat roof are in place before the first day on site.
The work itself
Our trades complete a new flat roof while your point of contact keeps you updated. When everything is finished, we clear the site, take away waste and go through the result with you before handover.
What you can expect from us
Frequently asked questions
Should I insulate my flat roof when it is replaced?
Replacing a flat roof is the most cost-effective time to add insulation, because the covering is already off. A warm roof, with insulation laid above the deck, keeps the structure warm and reduces condensation risk. Building regulations may require insulation when a large part of the roof is renewed. It raises the roof height slightly, which affects trims and upstands.
Why does water sit on my flat roof?
Ponding water on a flat roof is usually caused by inadequate falls, sagging joists, a deck that has dipped or blocked outlets. Small puddles that dry within a day or two are not always a problem, but standing water speeds up wear and finds any weakness. A new roof can be laid on firring strips or tapered insulation to create proper falls. We check falls during the survey.
Can you repair my flat roof instead of replacing it?
A flat roof can often be repaired if the damage is limited to a small split, a failed joint or a loose upstand and the rest of the covering is sound. If the deck is soft, the covering is blistered or cracked across the roof, or leaks keep returning, replacement is usually better value. We assess the whole roof and give you an honest recommendation.
What happens at the survey?
We visit your home at a time that suits you, look at the area involved, take measurements and check access, condition and any services that might be affected. We talk through what you want from a new flat roof, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
Is the price fixed?
Yes, for the specification we agree. Your written quote sets out exactly what is included at a fixed price. It only changes if you ask for something different, or if a problem the survey could not reasonably reveal later needs extra work. In either case we explain the change and confirm it in writing before going ahead.
Towns in Northamptonshire
Find your town below. Every place listed in Northamptonshire is covered for a new flat roof, with the same survey, written quote and fixed-price process.

