Stevenage at a glance
- Postcode districts
- SG1, SG2
- Population
- about 91,774 (GeoNames)
- Council area
- Stevenage Borough Council
- Building approval
- Stevenage Borough Council building control, or a registered building control approver
- Nearest main town
- Luton, about 9 miles
- Guide price region
- East of England (+5% on West Midlands rates)
When should a flat roof in Stevenage be replaced?
A sensible moment to replace a flat roof in Stevenage 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.
Around Stevenage, flat roofs are common on newer estates where the first extension roofs are now being replaced and on shops with flat-roofed rear stores below flats. 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 Stevenage?
Guide price in Stevenage: £2,950–£5,150 for a 20 m² extension roof in EPDM with a new deck and insulation, including VAT at East of England 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 | £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 |
Do I need building regulations approval to replace a flat roof?
Often, yes. Replacing the covering of a flat roof over a heated room is usually treated as renovating a thermal element, which brings insulation requirements and, in most cases, approval.
In England, if more than half of that roof is renovated, the whole roof should be upgraded towards a U-value of 0.16 W/m²K for homes (0.18 for non-domestic buildings) where that is technically, functionally and economically feasible, judged against a simple payback of 15 years. Approval comes from building control or self-certification through a registered competent person scheme. Structural changes, or a covering that adds 15% or more to the roof's weight, also need approval.
The other nations differ: most re-roofing in Wales needs approval, Scotland works through building standards and the building warrant, and in Northern Ireland you contact the district council's building control first. An unheated detached garage is not normally a thermal element. Planning permission is not usually needed if the roof looks much the same afterwards, though listed buildings and conservation areas are different. We handle approvals where needed; see building regulations.
What's included?
- Free survey of the deck, falls, edges and insulation
- Fixed written quote listing the full build-up
- Building control handled where needed, plus a written workmanship guarantee
- New deck, firrings and warm-roof insulation where needed
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?
- Hitchin · 5 mi
- Letchworth Garden City · 5 mi
- Welwyn Garden City · 7 mi
- Harpenden · 9 mi
- Hertford · 9 mi
- Luton · 9 mi
Flat roof replacement in Stevenage: questions
Do you cover Stevenage?
Yes. Stevenage is part of our Hertfordshire coverage, including postcode districts SG1, SG2. 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 Stevenage?
Where the work needs approval it goes to Stevenage 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 Stevenage?
£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.
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.
What time of year is best for a flat roof replacement?
Late spring to early autumn gives the most reliable dry spells, but a roof can be replaced in any season when the forecast allows. Adhesives and resins have minimum application temperatures, so winter work is planned around mild, dry days.