Letchworth Garden City at a glance
- Postcode districts
- SG6
- Population
- about 33,990 (GeoNames)
- Council area
- North Hertfordshire District Council
- Building approval
- North Hertfordshire District Council building control, or a registered building control approver
- Nearest main town
- Stevenage, about 5 miles
- Guide price region
- East of England (+5% on West Midlands rates)
When should a flat roof in Letchworth Garden City be replaced?
Flat roofs in Letchworth Garden City get replaced for the same reasons as anywhere else: the covering has reached the end of its service life, leaks keep returning after repairs, or water ponds because the deck has sagged. Once the boards are soft or the insulation is wet, a full strip usually costs less than another round of patching.
Around Letchworth Garden City, flat roofs are common on low-rise post-war blocks of flats and on 1960s and 1970s link-detached houses with flat-roofed garages and porches. The East of England is the driest part of Britain, with parts of the Anglian region around 630 mm a year, so summer heat and UV, not rainfall, do most of the ageing on a felt roof.
How much does a flat roof replacement cost in Letchworth Garden City?
At East of England guide rates, a 20 m² extension roof in EPDM with a new deck and insulation comes to £2,950–£5,150 including VAT. 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 | £2,950–£5,150 |
| Single garage (18 m²), torch-on felt | £1,600–£2,750 |
| Extension (20 m²), GRP, new deck + insulation | £3,150–£5,650 |
| Single garage (18 m²), EPDM rubber | £1,700–£2,950 |
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?
- New membrane, upstands, edge trims and outlets
- Fixed written quote listing the full build-up
- Building control handled where needed, plus a written workmanship guarantee
- Strip-out of the old covering, with waste and skip
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?
Flat roof replacement in Letchworth Garden City: questions
Do you cover Letchworth Garden City?
Yes. Letchworth Garden City is part of our Hertfordshire coverage, including postcode districts SG6. 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 Letchworth Garden City?
Where the work needs approval it goes to North Hertfordshire 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 Letchworth Garden City?
£2,950–£5,150 for a 20 m² extension roof in EPDM with a new deck and insulation, at East of England guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
What guarantees come with a replacement roof?
Every re-roof comes with a written workmanship guarantee, with the length set out in your quote. Manufacturer material guarantees are available on many systems and we register them for you where the system allows; ask about insurance-backed options too.
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.