Flat RoofingContractors

Upgrades

Green and sedum roofs in Ely

Can your flat roof in Ely carry a green roof? It depends on the joists, the spans and the deck. We check the structure first, tell you if strengthening or an engineer's input is needed, and only then quote for the waterproofing and sedum build-up.

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

Ely at a glance

Postcode districts
CB7
Population
about 20,574 (GeoNames)
Council area
East Cambridgeshire District Council
Building approval
East Cambridgeshire District Council building control, or a registered building control approver
Nearest main town
Cambridge, about 15 miles
Guide price region
East of England (+5% on West Midlands rates)

Why choose a green roof in Ely?

Homeowners in Ely 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 and around Ely, flat roofs are typically found on low-rise post-war blocks of flats, and on shops with flat-roofed rear stores below flats. 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 Ely?

At East of England guide rates, a 20 m² insulated extension roof finished as a sedum green roof comes to £4,650–£8,500 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£4,650–£8,500
Extension (20 m²), EPDM, new deck + insulation£2,950–£5,150

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.

What's included?

  • Warm or inverted build-up to suit the roof
  • Pre-grown sedum blankets laid and watered in
  • Root-resistant membrane or separate root barrier
  • Drainage layer, filter and lightweight growing medium

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 Ely: questions

Do you cover Ely?

Yes. Ely is part of our Cambridgeshire coverage, including postcode districts CB7. 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 Ely?

Where the work needs approval it goes to East Cambridgeshire District 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 Ely?

£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.

What happens if a green roof needs repairing?

The green layers are lifted around the problem area, the membrane is repaired, and the layers are relaid. Building on a sound, long-life membrane in the first place keeps that to a minimum.

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.

Other flat roof work in Ely

Green and sedum roofs in Ely: get a fixed price

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

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