Bartley Green at a glance
- Postcode districts
- B32
- Population
- about 22,670 (GeoNames)
- Council area
- Birmingham City Council
- Building approval
- Birmingham City Council building control, or a registered building control approver
- Nearest main town
- Birmingham, about 5 miles
- Guide price region
- West Midlands (baseline rates)
What makes a good extension roof in Bartley Green?
Condensation drives some replacements in Bartley Green. 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.
Bartley Green's flat roofs are mostly on 1930s semis with flat-roofed garages and kitchen extensions, with plenty on 1960s and 1970s link-detached houses with flat-roofed garages and porches too. England averages roughly 870 mm of rain a year and the West Midlands sits close to that, so falls and outlets are the difference between a roof that drains and one that ponds.
How much does a new extension roof cost in Bartley Green?
For Bartley Green we use West Midlands rates: £2,800–£4,900 is the guide for a 20 m² extension roof in EPDM with a new deck and insulation, VAT included. 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 | £2,800–£4,900 |
| Extension (20 m²), GRP, new deck + insulation | £3,000–£5,400 |
| Extension (20 m²), EPDM, insulation + 1 rooflight upstand | £3,000–£5,250 |
| Single garage (18 m²), EPDM rubber | £1,600–£2,800 |
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?
- Free survey of the roof, abutment and room below
- Staged strip-out so the room stays weathertight
- New deck, vapour control layer and warm-roof insulation
- New abutment upstand and flashing, plus rebuilt rooflight kerbs
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?
- Halesowen · 2 mi
- Smethwick · 4 mi
- Birmingham · 5 mi
- Dudley · 6 mi
- West Bromwich · 6 mi
- Brierley Hill · 6 mi
Extension and kitchen roofs in Bartley Green: questions
Do you cover Bartley Green?
Yes. Bartley Green is part of our West Midlands coverage, including postcode districts B32. 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 Bartley Green?
Where the work needs approval it goes to Birmingham City 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 Bartley Green?
£2,800–£4,900 for a 20 m² extension roof in EPDM with a new deck and insulation, at West Midlands guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
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.
Is EPDM or GRP better for a kitchen extension?
Neither is better in every case. EPDM suits simple rectangular roofs with few details, while GRP is often chosen where there are rooflights, corners or occasional foot traffic.