- Guide price
- £4,400–£8,100
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
West Midlands at a glance
- Largest towns
- Birmingham, Coventry, Wolverhampton, Dudley
- Postcode areas
- B, CV, DY, WS, WV
- Building control
- Birmingham City Council, Coventry City Council, City of Wolverhampton Council and 4 other councils
- Neighbouring areas
- Worcestershire · Warwickshire · Staffordshire · Shropshire
- Guide price region
- West Midlands (baseline rates)
How much does a green roof cost in West Midlands?
Guide prices including VAT at West Midlands rates. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Extension (20 m²), EPDM with sedum green roof | £4,400–£8,100 |
| Extension (20 m²), EPDM, new deck + insulation | £2,800–£4,900 |
Which flat roofs are common in West Midlands?
Flat roofs in West Midlands sit on shops with flat-roofed rear stores below flats, 1960s and 1970s link-detached houses with flat-roofed garages and porches and terraced streets with flat-roofed rear kitchens and bathrooms. 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. 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 West Midlands the application goes to Birmingham City Council, Coventry City Council, City of Wolverhampton Council and 4 other councils. More on the rules.
Can my flat roof take the weight of a green roof?
Not every roof can, which is why we check the structure before quoting. A sedum roof is light compared with an intensive garden, but its growing medium holds water, and a saturated build-up adds significant weight to the roof.
We look at the joist sizes, spans and spacing, the condition of the deck and what the roof sits on. On a recently built extension with generously sized joists, an extensive green roof may be straightforward. On an older garage or a roof with undersized or rotten timbers, the structure may need strengthening, or a structural engineer's calculation may be needed before we can go ahead.
In England, a new roof covering that adds 15% or more to the weight of the roof triggers building control approval, and a green roof will often fall into that category. We handle building control where it is needed. The building regulations page covers the approval routes in each nation.
How long does a green roof last and how much maintenance does it need?
A well-built extensive green roof needs one or two maintenance visits a year, and the plant layer can help protect the membrane from sunlight and temperature swings.
Typical maintenance means pulling out weeds and tree seedlings before they root, clearing outlets and the gravel strips around edges, filling in any bare patches, and adding a slow-release feed if the sedum looks thin. Sedum is drought-tolerant once established, but newly laid blankets may need watering in a long dry spell during the first season.
The waterproofing underneath has the same expected life as on any other roof of that system. A green roof also slows down rainwater run-off from the roof and, when sedum flowers, attracts bees and other insects. Some councils encourage green roofs for those reasons, so it is worth mentioning one in a planning application for a new extension. Our maintenance guide covers routine checks.
Which towns in West Midlands do we cover?
- Birmingham
- Coventry
- Wolverhampton
- Dudley
- Walsall
- Solihull
- Sutton Coldfield
- West Bromwich
- Halesowen
- Stourbridge
- Smethwick
- Willenhall
- Tipton
- Bloxwich
- Washwood Heath
- Shirley
- Brierley Hill
- Aldridge
- Acocks Green
- Bartley Green
- Wednesbury
- Kingswinford
Green and sedum roofs in West Midlands: questions
Which towns in West Midlands do you cover?
All of West Midlands. 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 green roof cost in West Midlands?
£4,400–£8,100 for a 20 m² insulated extension roof finished as a sedum green roof, at West Midlands 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 West Midlands?
It depends on where the roof is: in West Midlands that's Birmingham City Council, Coventry City Council, City of Wolverhampton Council and 4 other councils. 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.
Does a green roof leak more than a normal flat roof?
No, as long as it is built correctly. The waterproofing beneath is what keeps water out, and the green layers protect it from sun and weather. The main risk is building it on a weak or ageing membrane.
Do I need to water a sedum roof?
Usually only in the first season, during long dry spells, while the blankets establish. After that, sedum copes with dry weather well.
Can I walk on a green roof?
Only for maintenance, and only where it is safe. Most extensive green roofs on homes aren't designed as roof terraces, and a terrace generally needs planning permission and edge protection.
Everything about green and sedum roofs → · All flat roofing in West Midlands →