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.
For a homeowner in Hampton, planning a new flat roof tends to begin with two questions: what will it cost, and how disruptive will it be? Our guide range is £2,600–£5,800 including VAT, and a typical job runs to 1–3 days for most roofs. Both numbers firm up once we have seen the property, measured up and agreed exactly what is included.
- Guide price
- £2,600–£5,800 inc VAT
- Time on site
- 1–3 days for most roofs
- Postcodes
- KT7, KT8, TW11, TW12 and TW13
- Planning rules
- England
- Local area
- Greater London
- Survey
- Free, with a written quote
What should you budget for a new flat roof in Hampton?
Prices for a new flat roof vary from house to house, but in Hampton most projects fall within £2,600–£5,800 including VAT. That reflects costs in London, about 30% above the national guide. Treat the table as a budgeting aid; the written figure follows a survey we carry out for free.
| Type of job | What it usually involves | Guide in Hampton |
|---|---|---|
| Small roof (up to 8m²) | A dormer, bay, porch or small garage roof re-covered in EPDM or GRP. | £1,050–£2,600 |
| Extension or garage (15–25m²) | A typical extension or single garage roof stripped and re-covered. | £2,600–£5,800 |
| Large or new warm roof | Larger roofs, or roofs needing a new deck and insulation build-up. | £5,200–£11,500 |
What moves the price up or down:
- Roof area and access to the roof
- Covering system: EPDM, GRP or torch-on felt
- Insulation upgrades and changes to roof height at edges
- Number of rooflights, pipes and upstands to detail
What does the job include in Hampton?
- Survey of the covering, deck, falls, upstands and drainage
- Stripping and disposal of the old roof covering
- Replacement of rotten or soft deck boards
- Insulation upgrade to a warm roof build-up where agreed
- New EPDM, GRP or torch-on felt membrane laid to falls
- New trims, outlets and gutter connections
Local housing and a new flat roof
London's housing is dominated by Victorian and Edwardian terraces, often in yellow London stock brick, with Georgian terraces in central districts and mansion blocks across many inner areas. Outer boroughs have large belts of interwar semis, and there are extensive post-war council estates. Many houses have been split into flats, and conservation areas are widespread.
Terraces suit side-return extensions and rear dormer loft conversions; interwar semis commonly take hip-to-gable lofts. Shared party walls, restricted parking and conservation rules often shape the plans and the programme.
For a new flat roof in Hampton, this means checking things like wall construction, roof structure and existing services before we put a figure on paper.
Planning and building rules in Hampton
Planning law differs across the UK. For a home in Hampton, it is the England rules below that count, and we check them with the council ahead of any 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?
Survey and measure
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
We put everything into a written, fixed-price quote: the specification, what's excluded, staged payments and the expected time on site. Take whatever time you need to decide; there's no pressure to commit.
Plan and prepare
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.
On site to finish
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
Questions about a new flat roof in Hampton
Which is better, EPDM rubber or GRP fibreglass?
EPDM rubber and GRP fibreglass are both reliable modern flat roof systems. EPDM is a single flexible sheet with very few joints, which copes well with movement and suits most extensions and garages. GRP is a hard, seamless finish that copes better with foot traffic and complex shapes, but needs dry weather to apply. Felt costs less but usually lasts less long. We recommend a system after seeing your roof.
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.
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.
How much does a new flat roof cost?
Re-covering a typical 15–25m² extension or garage roof costs £2,600–£5,800. As a guide, allow around £75–£170 per square metre plus fixed costs for stripping, waste and access, with torch-on felt at the lower end and GRP or EPDM with new decking or insulation at the top. Small dormer and porch roofs cost less overall but more per square metre. We confirm a fixed price after the survey.
Do I need planning permission in Hampton?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. Hampton is in England, so England's rules apply. Many smaller jobs need no planning application, but some still need building control approval. We check what applies to your address before quoting.
Also covering areas around Hampton
Whether you're in the centre of Hampton or on its outskirts, KT7, KT8, TW11 and TW12 addresses are covered. We extend the same service, and the same fixed-price approach, to West Molesey, East Molesey and Hanworth.

