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Green and sedum roofs in Slough

In Slough and across Berkshire, green roofs suit new rear extensions and garden buildings particularly well. We install the full build-up: deck, insulation, root-resistant membrane, drainage, growing medium and pre-grown sedum blankets, with gravel strips kept clear around edges and outlets.

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

Slough at a glance

Postcode districts
SL1, SL2, SL3
Population
about 164,793 (GeoNames)
Council area
Slough Borough Council
Building approval
Slough Borough Council building control, or a registered building control approver
Nearest main town
Reading, about 17 miles
Guide price region
South East (+10% on West Midlands rates)

Why choose a green roof in Slough?

In a place like Slough, many people look out over a flat extension or garage roof from upstairs. Grey felt or rubber isn't much of a view, and a sedum roof turns it into something green that changes colour through the seasons and flowers in summer.

Around Slough, flat roofs are common on terraced streets with flat-roofed rear kitchens and bathrooms and on shops with flat-roofed rear stores below flats. 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 Slough?

For Slough 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
  • Pre-grown sedum blankets laid and watered in
  • Drainage layer, filter and lightweight growing medium
  • Root-resistant membrane or separate root barrier

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 Slough: questions

Do you cover Slough?

Yes. Slough is part of our Berkshire coverage, including postcode districts SL1, SL2, SL3. 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 Slough?

Where the work needs approval it goes to Slough 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 Slough?

£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.

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.

Other flat roof work in Slough

Green and sedum roofs in Slough: get a fixed price

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

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