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Green and sedum roofs in Faversham

A green roof in Faversham looks best when it starts from a properly built flat roof. That is why we treat the waterproofing as the main job and the sedum as the finish, using a warm or inverted build-up to suit your roof and a root barrier where the membrane needs one.

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

Faversham at a glance

Postcode districts
ME13
Population
about 23,024 (GeoNames)
Council area
Swale Borough Council
Building approval
Swale Borough Council building control, or a registered building control approver
Nearest main town
Gillingham, about 16 miles
Guide price region
South East (+10% on West Midlands rates)

Why choose a green roof in Faversham?

Garden rooms and outbuildings in Faversham, 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.

Faversham's flat roofs are mostly on newer estates where the first extension roofs are now being replaced, with plenty on 1960s and 1970s link-detached houses with flat-roofed garages and porches too. Much of the South East sits in the drier Thames catchment at roughly 730 mm of rain a year, so the usual failures are at joints, upstands and outlets rather than from sheer volume of rain.

How much does a green roof cost in Faversham?

For Faversham we use South East rates: £4,850–£8,900 is the guide for a 20 m² insulated extension roof finished as a sedum green roof, VAT included. 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£4,850–£8,900
Extension (20 m²), EPDM, new deck + insulation£3,100–£5,350

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
  • Structural check of joists, deck and supports
  • Root-resistant membrane or separate root barrier
  • Warm or inverted build-up to suit the roof

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 Faversham: questions

Do you cover Faversham?

Yes. Faversham is part of our Kent coverage, including postcode districts ME13. 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 Faversham?

Where the work needs approval it goes to Swale 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 Faversham?

£4,850–£8,900 for a 20 m² insulated extension roof finished as a sedum green roof, at South East 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.

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.

Other flat roof work in Faversham

Green and sedum roofs in Faversham: get a fixed price

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

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