Port Glasgow at a glance
- Postcode districts
- PA14
- Population
- about 14,200 (GeoNames)
- Council area
- Inverclyde Council
- Building approval
- Inverclyde Council building standards
- Nearest main town
- Greenock, about 3 miles
- Guide price region
- Scotland (−5% on West Midlands rates)
Why choose a green roof in Port Glasgow?
If you're replacing an old flat roof in Port Glasgow, it's worth deciding whether to add sedum at the same time. If the structure can take it, that is the ideal moment, because the waterproofing is new and the green layers won't need lifting for a long time.
In and around Port Glasgow, flat roofs are typically found on newer estates where the first extension roofs are now being replaced, and on shops with flat-roofed rear stores below flats. Scotland averages roughly 1,570 mm of rain a year, with the west far wetter than the east, so drainage, falls and wind uplift are part of every specification we write.
How much does a green roof cost in Port Glasgow?
For Port Glasgow we use Scotland rates: £4,200–£7,700 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.
| Job | Guide 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
- Warm or inverted build-up to suit the roof
- Pre-grown sedum blankets laid and watered in
- Drainage layer, filter and lightweight growing medium
Building standards in Scotland
In Scotland the building standards technical handbooks (Section 6 for energy) apply, and the council's building standards service decides whether a building warrant is needed. Like-for-like repairs to a roof covering can be exempt; alterations, structural work and new roofs usually need a warrant before work starts. The domestic roof benchmark is 0.12 W/m²K, applied as far as reasonably practicable on an existing roof. More on the rules.
Which nearby areas do we also cover?
Green and sedum roofs in Port Glasgow: questions
Do you cover Port Glasgow?
Yes. Port Glasgow is part of our Inverclyde coverage, including postcode districts PA14. Surveys and roofs are carried out by vetted roofing teams working under S&K Property Investments and Improvement Ltd.
Who checks building standards for a flat roof in Port Glasgow?
Where the work needs approval it goes to Inverclyde Council building standards. 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 Port Glasgow?
£4,200–£7,700 for a 20 m² insulated extension roof finished as a sedum green roof, at Scotland guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can you put a green roof on a pitched roof?
We install green roofs on flat roofs only. Sloping green roofs need extra restraint to stop the growing medium slipping, and they are a specialist job outside our work.
Can a green roof have a rooflight in it?
Yes. The rooflight sits on a raised upstand with a gravel strip around it, so the planting stays clear of the glazing and the upstand stays visible and dry.