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Upgrades

Green and sedum roofs in Barnsley

We build sedum green roofs in Barnsley 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

Barnsley at a glance

Postcode districts
S70, S71, S72, S73, S74, S75
Population
about 71,447 (GeoNames)
Council area
Barnsley Council
Building approval
Barnsley Council building control, or a registered building control approver
Nearest main town
Wakefield, about 9 miles
Guide price region
Yorkshire and the Humber (−5% on West Midlands rates)

Why choose a green roof in Barnsley?

Homeowners in Barnsley 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 Barnsley, flat roofs are typically found on bungalows with flat-roofed side extensions and dormers, and on shops with flat-roofed rear stores below flats. England averages roughly 870 mm of rain a year; the Pennine side of Yorkshire is wetter and windier than the east, so we specify for the site rather than the county.

How much does a green roof cost in Barnsley?

At Yorkshire and the Humber 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?

  • Root-resistant membrane or separate root barrier
  • Gravel strips kept clear around edges and outlets
  • Pre-grown sedum blankets laid and watered in
  • 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 Barnsley: questions

Do you cover Barnsley?

Yes. Barnsley is part of our South Yorkshire coverage, including postcode districts S70, S71, S72, S73, S74, S75. 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 Barnsley?

Where the work needs approval it goes to Barnsley 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 Barnsley?

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

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.

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.

Other flat roof work in Barnsley

Green and sedum roofs in Barnsley: get a fixed price

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

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