Durham at a glance
- Postcode districts
- DH1
- Population
- about 47,785 (GeoNames)
- Council area
- Durham County Council
- Building approval
- Durham County Council building control, or a registered building control approver
- Nearest main town
- Sunderland, about 12 miles
- Guide price region
- North East (−7% on West Midlands rates)
What makes a good extension roof in Durham?
Condensation drives some replacements in Durham. 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.
In a town like Durham, flat roofs are commonly found on newer estates where the first extension roofs are now being replaced or 1960s and 1970s link-detached houses with flat-roofed garages and porches. England averages roughly 870 mm of rain a year; the North East is drier than the west but cold and windy near the coast, so wind uplift and freeze-thaw are in the specification.
How much does a new extension roof cost in Durham?
Guide price in Durham: £2,600–£4,550 for a 20 m² extension roof in EPDM with a new deck and insulation, including VAT at North East 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 | £2,600–£4,550 |
| Extension (20 m²), GRP, new deck + insulation | £2,800–£5,000 |
| Extension (20 m²), EPDM, insulation + 1 rooflight upstand | £2,800–£4,850 |
| Single garage (18 m²), EPDM rubber | £1,500–£2,600 |
Which flat roof system suits a kitchen extension?
On a plain rectangular extension, EPDM rubber is a strong, quiet choice that can often be laid in one sheet. It handles the slight movement between an extension and the house well.
Where the roof has a lantern, several rooflights or an internal corner, GRP fibreglass forms neat, rigid details around each one. Torch-on felt is a proven layered system and keeps costs down, though near timber cladding or at fragile junctions we may prefer a cold-applied method. If the extension is overlooked from upstairs windows, a sedum green roof is worth considering, provided the structure can take the extra load.
Whatever the membrane, the insulation sits above the deck as a warm roof. Our warm vs cold roof guide explains why.
What's included?
- Building control handled where needed, and a written workmanship guarantee
- New deck, vapour control layer and warm-roof insulation
- New abutment upstand and flashing, plus rebuilt rooflight kerbs
- Free survey of the roof, abutment and room below
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?
- Spennymoor · 5 mi
- Chester-le-Street · 6 mi
- Houghton-Le-Spring · 6 mi
- Stanley · 8 mi
- Washington · 9 mi
- Bishop Auckland · 9 mi
Extension and kitchen roofs in Durham: questions
Do you cover Durham?
Yes. Durham is part of our County Durham coverage, including postcode districts DH1. 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 Durham?
Where the work needs approval it goes to Durham County 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 Durham?
£2,600–£4,550 for a 20 m² extension roof in EPDM with a new deck and insulation, at North East 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.
Can you keep my existing roof lantern?
Often, if the lantern itself is sound. We lift it, rebuild the kerb, dress the new membrane up the upstand and refit the lantern.