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Upgrades

Green and sedum roofs in Huntingdon

We build sedum green roofs in Huntingdon on extensions, garages, garden rooms and outbuildings, as part of a new flat roof. Every job begins with a structural check and new, root-resistant waterproofing, so the planting sits on a roof that is designed to carry it and keep water out.

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

Huntingdon at a glance

Postcode districts
PE28, PE29
Population
about 23,937 (GeoNames)
Council area
Huntingdonshire District Council
Building approval
Huntingdonshire District Council building control, or a registered building control approver
Nearest main town
Cambridge, about 16 miles
Guide price region
East of England (+5% on West Midlands rates)

Why choose a green roof in Huntingdon?

Rainwater from flat roofs in Huntingdon runs off quickly in heavy showers. A green roof holds some of that water back and releases it more slowly, which is one reason some owners and developers choose one. The flowering sedum also draws in bees and other insects.

In a town like Huntingdon, flat roofs are commonly found on 1960s and 1970s link-detached houses with flat-roofed garages and porches or terraced streets with flat-roofed rear kitchens and bathrooms. 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 Huntingdon?

Guide price in Huntingdon: £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.

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

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?

  • Gravel strips kept clear around edges and outlets
  • Pre-grown sedum blankets laid and watered in
  • Root-resistant membrane or separate root barrier
  • Structural check of joists, deck and supports

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 Huntingdon: questions

Do you cover Huntingdon?

Yes. Huntingdon is part of our Cambridgeshire coverage, including postcode districts PE28, PE29. 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 Huntingdon?

Where the work needs approval it goes to Huntingdonshire 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 Huntingdon?

£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 green roof on a pitched roof?

We install green roofs on flat roofs only. Sloping green roofs need extra restraint to stop the growing medium slipping, and they are a specialist job outside our work.

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 Huntingdon

Green and sedum roofs in Huntingdon: get a fixed price

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

Call usGet a guide price