Flat RoofingContractors

Upgrades

Green and sedum roofs in Woking

A sedum roof suits an extension in Woking 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

Woking at a glance

Postcode districts
GU21, GU22
Population
about 103,900 (GeoNames)
Council area
Woking Borough Council
Building approval
Woking Borough Council building control, or a registered building control approver
Nearest main town
Slough, about 13 miles
Guide price region
South East (+10% on West Midlands rates)

Why choose a green roof in Woking?

Homeowners in Woking 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 a large town like Woking, flat roofs are commonly found on lock-up garage blocks on estates or 1930s semis with flat-roofed garages and kitchen extensions. 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 Woking?

At South East guide rates, a 20 m² insulated extension roof finished as a sedum green roof comes to £4,850–£8,900 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£4,850–£8,900
Extension (20 m²), EPDM, new deck + insulation£3,100–£5,350

Can a green roof go on my existing flat roof?

Only if the existing waterproofing is sound, root-resistant or protected by a root barrier, and has plenty of life left. In most cases it makes more sense to lay a green roof as part of a replacement.

Once the sedum, substrate and drainage layers are down, the membrane underneath is hard to inspect and expensive to repair, because the green layers have to be lifted to get to it. Putting a green roof on an ageing covering risks paying for the greenery twice. Our repair or replace guide helps you judge whether your current roof is a sensible base.

As for planning, re-covering a house roof normally needs no application if its appearance doesn't change materially. Because a green roof does change how a roof looks, check with your council, especially for listed buildings, conservation areas and roofs that are easily seen. The planning guide has more.

What's included?

  • Root-resistant membrane or separate root barrier
  • Warm or inverted build-up to suit the roof
  • Drainage layer, filter and lightweight growing medium
  • 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 Woking: questions

Do you cover Woking?

Yes. Woking is part of our Surrey coverage, including postcode districts GU21, GU22. 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 Woking?

Where the work needs approval it goes to Woking 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 Woking?

£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.

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.

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 Woking

Green and sedum roofs in Woking: get a fixed price

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

Call usGet a guide price