Egham at a glance
- Postcode districts
- TW20
- Population
- about 29,663 (GeoNames)
- Council area
- Runnymede Borough Council
- Building approval
- Runnymede Borough Council building control, or a registered building control approver
- Nearest main town
- Slough, about 6 miles
- Guide price region
- South East (+10% on West Midlands rates)
When should a flat roof in Egham be replaced?
A sensible moment to replace a flat roof in Egham is when other work is planned on the house, such as a kitchen refit below, new windows or a loft conversion. Doing the roof first protects the new work, and it is the natural time to upgrade insulation to the level the regulations expect for a renovated roof.
In a town like Egham, flat roofs are commonly found on low-rise post-war blocks of flats or bungalows with flat-roofed side extensions and dormers. 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 Egham?
For Egham we use South East rates: £3,100–£5,350 is the guide for a 20 m² extension roof in EPDM with a new deck and insulation, VAT included. 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?
- Fixed written quote listing the full build-up
- New deck, firrings and warm-roof insulation where needed
- Free survey of the deck, falls, edges and insulation
- Building control handled where needed, plus a written workmanship guarantee
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?
- Staines-upon-Thames · 2 mi
- Chertsey · 4 mi
- Ashford, Surrey · 4 mi
- Windsor · 4 mi
- Ascot · 5 mi
- Slough · 6 mi
Flat roof replacement in Egham: questions
Do you cover Egham?
Yes. Egham is part of our Surrey coverage, including postcode districts TW20. 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 Egham?
Where the work needs approval it goes to Runnymede Borough 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 Egham?
£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.
Is VAT charged on a flat roof replacement?
Yes, roof replacement is standard-rated at 20%, and an insulated replacement is treated as a single supply. Our guide prices already include VAT.
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.
