Wath upon Dearne at a glance
- Postcode districts
- S63
- Population
- about 16,964 (GeoNames)
- Council area
- Rotherham Council
- Building approval
- Rotherham Council building control, or a registered building control approver
- Nearest main town
- Rotherham, about 5 miles
- Guide price region
- Yorkshire and the Humber (−5% on West Midlands rates)
What makes a good extension roof in Wath upon Dearne?
Condensation drives some replacements in Wath upon Dearne. Older extension roofs were often built cold, with insulation between the joists and no reliable vapour control. Warm air from the kitchen reaches the cold deck, moisture builds up and the timber suffers. A warm roof deals with the cause, not just the stain.
Around Wath upon Dearne, flat roofs are common on newer estates where the first extension roofs are now being replaced and on bungalows with flat-roofed side extensions and dormers. 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 Wath upon Dearne?
Guide price in Wath upon Dearne: £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 |
Why does water pond or leak where the extension meets the house?
Usually because the fall runs the wrong way, the abutment detail has failed, or the roof has sagged close to the wall. The junction with the house is the most common leak point on an extension roof.
If the roof falls towards the house, or the deck dips near the wall, water sits against the upstand and finds any weakness in the flashing above. Older roofs often have the felt simply turned up the brickwork with no cover flashing, or a flashing that has pulled out of its joint. A patch will not change a fall. We re-firr or use tapered insulation so water runs away from the wall, then form a new upstand, usually 150 mm above the finished roof, with a flashing chased into the mortar joint.
Rooflights and lanterns are the other weak point. A lantern needs a properly built kerb with the membrane dressed up and under its frame. We rebuild rooflight upstands within the roof job; we do not supply the lantern itself. Our guide to ponding water explains the causes in more depth.
What's included?
- New abutment upstand and flashing, plus rebuilt rooflight kerbs
- Free survey of the roof, abutment and room below
- Building control handled where needed, and a written workmanship guarantee
- 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?
Extension and kitchen roofs in Wath upon Dearne: questions
Do you cover Wath upon Dearne?
Yes. Wath upon Dearne is part of our South Yorkshire coverage, including postcode districts S63. 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 Wath upon Dearne?
Where the work needs approval it goes to Rotherham 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 Wath upon Dearne?
£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.
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.
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.