- Guide price
- £2,650–£4,650
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
South Yorkshire at a glance
- Largest towns
- Sheffield, Rotherham, Doncaster, Barnsley
- Postcode areas
- DN, S
- Building control
- Sheffield City Council, Rotherham Council, City of Doncaster Council and 1 other council
- Neighbouring areas
- West Yorkshire · Derbyshire · Nottinghamshire · Greater Manchester
- Guide price region
- Yorkshire and the Humber (−5% on West Midlands rates)
How much does a new extension roof cost in South Yorkshire?
Guide prices 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 |
Which flat roofs are common in South Yorkshire?
Flat roofs in South Yorkshire sit on shops with flat-roofed rear stores below flats, lock-up garage blocks on estates and low-rise post-war blocks of flats. 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. Approximate 1991–2020 regional averages based on Met Office data.
Building regulations in England
Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. Renovated roofs over heated rooms are insulated to around 0.16 W/m²K where that's feasible, and new extension roofs are built to 0.15 W/m²K. In South Yorkshire the application goes to Sheffield City Council, Rotherham Council, City of Doncaster Council and 1 other council. More on the rules.
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.
Does an extension roof replacement need building regulations?
Usually, yes. An extension roof over a heated room is a thermal element, so replacing most of it typically brings insulation requirements and an approval route.
In England, renovating more than half of the roof means upgrading it towards 0.16 W/m²K where that is technically, functionally and economically feasible. The approval comes from building control or a competent person scheme. A brand-new extension roof is designed to 0.15. Wales usually requires approval for most re-roofing, with a renovation target of 0.16 and a new-extension target of 0.13. Scotland handles this through building standards and the warrant process, and Northern Ireland through district council building control.
Planning is not normally needed to re-cover an extension roof that looks broadly the same afterwards. Turning the roof into a terrace is another matter. We handle building control where the job needs it; see our building regulations page.
Which towns in South Yorkshire do we cover?
- Sheffield
- Rotherham
- Doncaster
- Barnsley
- Chapeltown
- Darton
- Dinnington
- Adwick le Street
- Nether Edge
- Rawmarsh
- Fulwood
- Maltby
- Thorne
- Wath upon Dearne
- Conisbrough
- Hoyland
- Wombwell
- Mexborough
Extension and kitchen roofs in South Yorkshire: questions
Which towns in South Yorkshire do you cover?
All of South Yorkshire. The main towns have their own pages below, and if yours isn't listed we still cover it: send your postcode and we'll confirm.
How much does a new extension roof cost in South Yorkshire?
£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.
Which council handles building control for a flat roof in South Yorkshire?
It depends on where the roof is: in South Yorkshire that's Sheffield City Council, Rotherham Council, City of Doncaster Council and 1 other council. Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. We confirm which applies at the survey.
Will a new extension roof sit higher than the old one?
Usually, by the thickness of the added insulation. We check the height against the upstairs window sills, door thresholds and wall flashings at survey so everything still works.
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.
How do I know my extension roof needs replacing rather than repairing?
Repeated leaks, a soft deck, wet insulation or widespread cracking point to replacement. A single defect on a dry, sound roof can usually be repaired.
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