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.
Whatever prompted you to look into a new flat roof, whether wear and tear, a growing family or plans to move, we can survey your Walton-on-Thames home and give you a price in writing. Homes in the South East typically come in at £2,200–£5,000, VAT included, for this kind of work. We also cover Sunbury-on-Thames, West Molesey and Weybridge, and the same steps apply wherever you are in Surrey.
- Guide price
- £2,200–£5,000 inc VAT
- Time on site
- 1–3 days for most roofs
- Postcodes
- KT8, KT12, KT13, TW16 and TW17
- Planning rules
- England
- Local area
- Surrey
- Survey
- Free, with a written quote
Flat roofs prices in Walton-on-Thames
The costs listed here are typical for a new flat roof around Walton-on-Thames and include VAT. They reflect labour and material costs in the South East, about 12% above the national guide, giving a range of £2,200–£5,000. Exact pricing depends on your home, so we only fix it once a free site survey is done.
| Type of job | What it usually involves | Guide in Walton-on-Thames |
|---|---|---|
| Small roof (up to 8m²) | A dormer, bay, porch or small garage roof re-covered in EPDM or GRP. | £900–£2,200 |
| Extension or garage (15–25m²) | A typical extension or single garage roof stripped and re-covered. | £2,200–£5,000 |
| Large or new warm roof | Larger roofs, or roofs needing a new deck and insulation build-up. | £4,500–£10,000 |
Your price depends mostly on:
- Roof area and access to the roof
- Covering system: EPDM, GRP or torch-on felt
- Condition of the deck and joists underneath
- Number of rooflights, pipes and upstands to detail
What does the job include in Walton-on-Thames?
- 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
- Upstands, flashings and drip edges finished neatly
- New trims, outlets and gutter connections
Local housing and a new flat roof
Surrey has many Victorian and Edwardian villas, interwar semis in the commuter towns near London, and Arts and Crafts houses with tile-hanging and tall chimneys. Bargate stone appears around Godalming, and large detached homes are common in Guildford, Woking, Weybridge and the Surrey Hills villages.
Mild and relatively dry, with clay soils in the north and Weald that can move in summer; mature trees near houses affect foundations.
These patterns matter for a new flat roof: older walls, roofs and floors in Walton-on-Thames can need different materials or extra preparation compared with newer homes.
Planning and building rules in Walton-on-Thames
Because Walton-on-Thames falls under England's rules, the guidance below is the version relevant to you. Before sending a price, we check your property's position with the council.
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.
The four stages
A visit to your home
First, someone visits your home in Walton-on-Thames to see the space, take measurements and note anything that could affect the work, such as access or the condition of what is there. There is no charge for this visit.
Price and scope agreed
After the survey we send a quote for a new flat roof that fixes the price for the scope we've agreed. If you want to change materials or scope, we revise it in writing before anything is booked.
Dates and permissions
Preparation matters as much as the build. We agree access, parking and working hours with you, order materials in good time, and confirm any permissions so the job isn't held up once it starts.
Finish and handover
The work is carried out to the agreed specification, with floors and furniture protected and the site kept tidy. At the end we clean up, walk through the finished job with you and hand over any certificates.
What you can expect from us
Questions about a new flat roof in Walton-on-Thames
How long does a flat roof last?
A well-installed EPDM or GRP flat roof can last 25 years or more, while torch-on felt systems typically last around 15–25 years, depending on quality and exposure. Lifespan depends on correct falls, good detailing at edges and upstands, and keeping outlets clear. Foot traffic, ponding and poor ventilation shorten it. Annual checks help catch small problems early.
Which postcodes in Walton-on-Thames do you cover?
We cover KT8, KT12, KT13 and TW16, along with the rest of Surrey. If your postcode is not listed, get in touch anyway: our coverage is UK-wide, and we can usually arrange a survey wherever you live. Enter your postcode in the guide-price tool or contact form and we will confirm.
How long will a new flat roof take?
On a typical home, allow 1–3 days for most roofs. Larger projects, older buildings and extra work found once things are opened up can extend that, while simpler jobs may be shorter. Your quote includes an estimate of time on site, and your point of contact keeps you updated on the programme as the work progresses.
How much does a new flat roof cost?
Re-covering a typical 15–25m² extension or garage roof costs £2,200–£5,000. 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.
How long does a flat roof replacement take?
Replacing a typical extension or garage flat roof usually takes one to three days. Stripping and any deck repairs come first, then insulation where agreed, the new membrane and the trims and outlets. GRP needs dry weather and time to cure, and we plan around the forecast. Larger roofs or roofs with many rooflights take longer. We confirm timing with your quote.
Also covering areas around Walton-on-Thames
Live in Walton-on-Thames? Our coverage takes in the KT8, KT12, KT13 and TW16 postcode areas and reaches out to Sunbury-on-Thames, West Molesey and Weybridge, so homes on the outskirts and in the next town along are included.

