Sevenoaks at a glance
- Postcode districts
- TN13
- Population
- about 29,506 (GeoNames)
- Council area
- Sevenoaks District Council
- Building approval
- Sevenoaks District Council building control, or a registered building control approver
- Nearest main town
- Maidstone, about 14 miles
- Guide price region
- South East (+10% on West Midlands rates)
When should a flat roof in Sevenoaks be replaced?
A mineral felt roof laid decades ago may still look intact from the ground in Sevenoaks, yet have lost its chippings, cracked at the laps and pulled away at the upstands. Those faults let water track under the covering, so by the time a ceiling stain appears, the deck has often been wet for some time.
In a town like Sevenoaks, flat roofs are commonly found on 1960s and 1970s link-detached houses with flat-roofed garages and porches or low-rise post-war blocks of flats. Much of the South East sits in the drier Thames catchment at roughly 730 mm of rain a year, so the usual failures are at joints, upstands and outlets rather than from sheer volume of rain.
How much does a flat roof replacement cost in Sevenoaks?
Guide price in Sevenoaks: £3,100–£5,350 for a 20 m² extension roof in EPDM with a new deck and insulation, including VAT at South East rates. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Extension (20 m²), EPDM, new deck + insulation | £3,100–£5,350 |
| Single garage (18 m²), torch-on felt | £1,650–£2,900 |
| Extension (20 m²), GRP, new deck + insulation | £3,300–£5,900 |
| Single garage (18 m²), EPDM rubber | £1,750–£3,100 |
Which system should I replace my flat roof with?
The right system depends on the roof's size, shape, use and number of details, so no single material suits every roof. These are the usual starting points:
- EPDM rubber suits simple, rectangular roofs, where one sheet can often cover the area with few or no joins.
- GRP fibreglass suits roofs with many corners, rooflights or edges, and gives a rigid surface for occasional maintenance traffic.
- Torch-on felt is a layered, hard-wearing system that keeps the cost down on larger or plain roofs.
- Liquid-applied systems handle awkward details and can overlay a sound existing surface.
- Single-ply and mastic asphalt are more usual on commercial roofs, blocks and terraces.
We recommend a system at survey and explain why. Our EPDM vs GRP vs felt guide sets out the trade-offs if you want to compare first.
What's included?
- Free survey of the deck, falls, edges and insulation
- New membrane, upstands, edge trims and outlets
- Strip-out of the old covering, with waste and skip
- Fixed written quote listing the full build-up
Building regulations in England
Replacing more than half of a flat roof over a heated room usually counts as renovating a thermal element, so the roof is insulated to around 0.16 W/m²K where that's technically and economically feasible, and the work is notified to building control: the council or a registered building control approver, unless a registered competent person self-certifies it. A roof on a new extension is built to 0.15 W/m²K. Patch repairs, and most unheated detached garages, don't trigger the upgrade. Structural changes, or a new covering that adds 15% or more to the roof's weight, also need approval. More on the rules.
Which nearby areas do we also cover?
- Tonbridge · 6 mi
- Swanley · 9 mi
- Longfield · 10 mi
- Royal Tunbridge Wells · 10 mi
- Caterham · 12 mi
- Dartford · 12 mi
Flat roof replacement in Sevenoaks: questions
Do you cover Sevenoaks?
Yes. Sevenoaks is part of our Kent coverage, including postcode districts TN13. Surveys and roofs are carried out by vetted roofing teams working under S&K Property Investments and Improvement Ltd.
Who checks building regulations for a flat roof in Sevenoaks?
Where the work needs approval it goes to Sevenoaks District Council building control, or a registered building control approver. We tell you at the survey whether your job needs it and deal with the paperwork as part of the quote.
How much does a flat roof replacement cost in Sevenoaks?
£3,100–£5,350 for a 20 m² extension roof in EPDM with a new deck and insulation, at South East guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Will a new flat roof be better insulated than the old one?
If it is over a heated room, yes. A full replacement usually has to be upgraded towards current insulation levels where feasible, and we build it as a warm roof with the insulation above the deck.
Will a replacement make my roof higher?
Usually a little, if insulation is added above the deck. We check door thresholds, window sills, upstands and wall flashings at survey so the new level works.