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Green and sedum roofs in Deeside

A sedum roof suits an extension in Deeside that is overlooked from upstairs windows, or a garden building you want to blend into the garden. We explain the weight, planning and maintenance points at the survey so the decision is a clear one.

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

Deeside at a glance

Postcode districts
CH5
Population
about 32,000 (GeoNames)
Council area
Flintshire County Council
Building approval
Flintshire County Council building control, or a registered building control approver
Nearest main town
Buckley, about 3 miles
Guide price region
Wales (−8% on West Midlands rates)

Why choose a green roof in Deeside?

Small commercial buildings and blocks in Deeside with a flat roof sometimes add an extensive green roof as part of a refurbishment. The structural check and safe access for maintenance matter even more on these larger roofs, which may need edge protection or fall-arrest points for each visit.

Deeside's flat roofs are mostly on bungalows with flat-roofed side extensions and dormers, with plenty on 1960s and 1970s link-detached houses with flat-roofed garages and porches too. Wales averages roughly 1,460 mm of rain a year, among the wettest in Britain, so we design for steady run-off: proper falls, clear outlets and upstands well above the finished roof.

How much does a green roof cost in Deeside?

Guide price in Deeside: £4,050–£7,450 for a 20 m² insulated extension roof finished as a sedum green roof, including VAT at Wales 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£4,050–£7,450
Extension (20 m²), EPDM, new deck + insulation£2,600–£4,500

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
  • Drainage layer, filter and lightweight growing medium
  • Warm or inverted build-up to suit the roof

Building regulations in Wales

The Welsh Approved Document L applies. Renovating more than half of a roof over a heated room means upgrading it to around 0.16 W/m²K where feasible, and new extension roofs are built to 0.13 W/m²K. Welsh Government guidance is that most re-roofing needs building control approval, so check whenever more than a quarter of a roof is replaced or repaired. We deal with the application as part of the job. More on the rules.

Which nearby areas do we also cover?

Green and sedum roofs in Deeside: questions

Do you cover Deeside?

Yes. Deeside is part of our Flintshire coverage, including postcode districts CH5. 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 Deeside?

Where the work needs approval it goes to Flintshire County 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 Deeside?

£4,050–£7,450 for a 20 m² insulated extension roof finished as a sedum green roof, at Wales 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.

Do I need to water a sedum roof?

Usually only in the first season, during long dry spells, while the blankets establish. After that, sedum copes with dry weather well.

Other flat roof work in Deeside

Green and sedum roofs in Deeside: get a fixed price

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

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