Thorne at a glance
- Postcode districts
- DN8
- Population
- about 17,295 (GeoNames)
- Council area
- City of Doncaster Council
- Building approval
- City of Doncaster Council building control, or a registered building control approver
- Nearest main town
- Doncaster, about 9 miles
- Guide price region
- Yorkshire and the Humber (−5% on West Midlands rates)
What makes a good extension roof in Thorne?
Ponding against the house wall is a common reason for replacing an extension roof in Thorne. When the deck dips near the wall or the fall runs the wrong way, water sits against the abutment and eventually gets in. A new roof with corrected falls moves the water to the gutter.
Thorne's flat roofs are mostly on terraced streets with flat-roofed rear kitchens and bathrooms, with plenty on newer estates where the first extension roofs are now being replaced too. England averages roughly 870 mm of rain a year; the Pennine side of Yorkshire is wetter and windier than the east, so we specify for the site rather than the county.
How much does a new extension roof cost in Thorne?
Guide price in Thorne: £2,650–£4,650 for a 20 m² extension roof in EPDM with a new deck and insulation, including VAT at Yorkshire and the Humber 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 | £2,650–£4,650 |
| Extension (20 m²), GRP, new deck + insulation | £2,850–£5,100 |
| Extension (20 m²), EPDM, insulation + 1 rooflight upstand | £2,850–£4,950 |
| Single garage (18 m²), EPDM rubber | £1,500–£2,650 |
How long will my kitchen be disrupted by a new roof?
Most single-storey extension roofs are replaced in two to four working days, depending on size, rooflights and weather. The kitchen usually stays in use throughout.
Expect noise during the strip-out, and occasional dust through gaps around old rooflights, so it helps to cover worktops and move anything fragile off high shelves. We strip only what we can make weathertight by the end of each day. If a rooflight or lantern is being lifted and refitted, there may be a temporary cover over the opening for a short time. Resin systems smell while they cure, so keep the windows below the roof closed on that day.
What's included?
- Building control handled where needed, and a written workmanship guarantee
- New deck, vapour control layer and warm-roof insulation
- Free survey of the roof, abutment and room below
- Falls set away from the house wall
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?
- Goole · 7 mi
- Doncaster · 9 mi
- Adwick le Street · 9 mi
- Selby · 13 mi
- Scunthorpe · 13 mi
- South Elmsall · 13 mi
Extension and kitchen roofs in Thorne: questions
Do you cover Thorne?
Yes. Thorne is part of our South Yorkshire coverage, including postcode districts DN8. 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 Thorne?
Where the work needs approval it goes to City of Doncaster 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 new extension roof cost in Thorne?
£2,650–£4,650 for a 20 m² extension roof in EPDM with a new deck and insulation, at Yorkshire and the Humber guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can a sedum roof go on my extension?
Possibly, if the structure can carry the extra weight and the roof has suitable falls and drainage. We check the joists at survey before recommending it.
Why does my extension ceiling get damp in winter if the roof isn't leaking?
That is often condensation in a cold roof, where warm, moist air reaches the cold underside of the deck. A warm-roof replacement with a vapour control layer usually solves it.