Flat RoofingContractors

Upgrades

Green and sedum roofs in Bury

A sedum roof suits an extension in Bury that is overlooked from upstairs windows, or a garden building you want to blend into the garden. We explain the weight, planning and maintenance points at the survey so the decision is a clear one.

Sedum green roof with a gravel border and inspection chamber on a single-storey extensionComputer-generated example image

Bury at a glance

Postcode districts
BL0, BL8, BL9, M25, M26, M45
Population
about 61,044 (GeoNames)
Council area
Bury Council
Building approval
Bury Council building control, or a registered building control approver
Nearest main town
Bolton, about 6 miles
Guide price region
North West (−5% on West Midlands rates)

Why choose a green roof in Bury?

Homeowners in Bury building a new extension may find a green roof can help with a planning application, as some councils encourage them for biodiversity and slower rainwater run-off. It is worth raising early with your designer, before the roof structure is drawn up, so the joists can be sized for the extra weight.

In a large town like Bury, flat roofs are commonly found on newer estates where the first extension roofs are now being replaced or low-rise post-war blocks of flats. The North West is one of England's wetter regions, averaging roughly 1,290 mm of rain a year, so falls, outlets and well-detailed upstands matter more than the membrane colour.

How much does a green roof cost in Bury?

At North West guide rates, a 20 m² insulated extension roof finished as a sedum green roof comes to £4,200–£7,700 including VAT. The fixed price comes after a free survey for new and replacement roofs.

JobGuide price inc VAT
Extension (20 m²), EPDM with sedum green roof£4,200–£7,700
Extension (20 m²), EPDM, new deck + insulation£2,650–£4,650

How is a green roof built on top of a flat roof?

From the bottom up, a green roof is a deck, a waterproofing system with root protection, then drainage, filter, growing medium and plants. The waterproofing does the job of keeping water out. The green layers sit above it.

  • Warm roof build-up: vapour control layer, insulation and waterproof membrane on the deck, then the green layers on top. This is the usual choice on a home extension being re-roofed.
  • Inverted build-up: waterproofing on the deck, then insulation boards designed to sit above it, then the green layers. This is common on terraces and some commercial roofs.
  • Root barrier: roots will exploit any weakness, so the membrane needs to be root-resistant. Some membranes are tested as root-resistant; others need a separate root barrier laid on top.
  • Drainage and edges: a drainage layer carries surplus water to outlets, and a gravel or pebble strip is usually left around edges, outlets, upstands and rooflights to keep them clear and accessible.

Upstands still need to rise around 150 mm above the finished surface, which on a green roof means above the top of the growing medium. We check that at the survey, alongside the external fire performance of the build-up where the roof is close to a boundary.

What's included?

  • Structural check of joists, deck and supports
  • Drainage layer, filter and lightweight growing medium
  • Root-resistant membrane or separate root barrier
  • 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?

Green and sedum roofs in Bury: questions

Do you cover Bury?

Yes. Bury is part of our Greater Manchester coverage, including postcode districts BL0, BL8, BL9, M25, M26, M45. 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 Bury?

Where the work needs approval it goes to Bury 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 Bury?

£4,200–£7,700 for a 20 m² insulated extension roof finished as a sedum green roof, at North West guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.

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.

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.

Other flat roof work in Bury

Green and sedum roofs in Bury: get a fixed price

Free survey and a written fixed quote for replacement and new roofs. No obligation.

Call usGet a guide price