Brentwood at a glance
- Postcode districts
- CM13, CM14, CM15
- Population
- about 52,586 (GeoNames)
- Council area
- Brentwood Borough Council
- Building approval
- Brentwood Borough Council building control, or a registered building control approver
- Nearest main town
- Basildon, about 7 miles
- Guide price region
- East of England (+5% on West Midlands rates)
Why choose a green roof in Brentwood?
Garden rooms and outbuildings in Brentwood, as elsewhere, often have small flat roofs that are seen from the house and garden. A sedum finish helps them blend in, provided the structure is strong enough and the roof underneath is built properly.
Brentwood's flat roofs are mostly on terraced streets with flat-roofed rear kitchens and bathrooms, with plenty on 1960s and 1970s link-detached houses with flat-roofed garages and porches too. The East of England is the driest part of Britain, with parts of the Anglian region around 630 mm a year, so summer heat and UV, not rainfall, do most of the ageing on a felt roof.
How much does a green roof cost in Brentwood?
Guide price in Brentwood: £4,650–£8,500 for a 20 m² insulated extension roof finished as a sedum green roof, including VAT at East of England 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 | £4,650–£8,500 |
| Extension (20 m²), EPDM, new deck + insulation | £2,950–£5,150 |
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.
What's included?
- Warm or inverted build-up to suit the roof
- Structural check of joists, deck and supports
- Drainage layer, filter and lightweight growing medium
- Pre-grown sedum blankets laid and watered in
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?
- Billericay · 5 mi
- Basildon · 7 mi
- South Ockendon · 8 mi
- Stanford-le-Hope · 9 mi
- Wickford · 9 mi
- Pitsea · 10 mi
Green and sedum roofs in Brentwood: questions
Do you cover Brentwood?
Yes. Brentwood is part of our Essex coverage, including postcode districts CM13, CM14, CM15. 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 Brentwood?
Where the work needs approval it goes to Brentwood Borough 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 green roof cost in Brentwood?
£4,650–£8,500 for a 20 m² insulated extension roof finished as a sedum green roof, at East of England guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can you put a sedum roof on a garage?
Often, yes, if the structure is strong enough. Many older garage roofs have light timbers, so a structural check comes first and strengthening may be needed.
Can a green roof have a rooflight in it?
Yes. The rooflight sits on a raised upstand with a gravel strip around it, so the planting stays clear of the glazing and the upstand stays visible and dry.