Brown and biodiverse roofs

Brown roofs are waterproofed and insulated in a similar way to a green roof.

Then a special substrate is added that mimics the brown-field site upon which the building was constructed.

The brown roof is then left for plants to self-collonise with plants and animals, helped by the wind or birds.

See: Living roof FAQ for more information.

Brown-field sites are often left undeveloped for many years, they will host a rich ecosystem of native plants and animal species, which will be severely impacted by development. Brown roofs recreate this environment.

Living roofs with deeper substrate and a mix of substrates, have a greater beneficial impact, improving invertebrate species richness e.g. spiders, beetles, sometimes rare species.

The creation of mounds provides refuge for invertebrates from extreme temperatures. Dead wood from trees felled creates habitats for stag beetles and other species.

Biodiverse roofs use a similar build and substrate to a brown roof, recreating the ‘brown field’ site that existed before the building was constructed.

Biodiverse roofs also include a crafted mix of seed or planting, often focusing on native species, specially formulated upon the recommendations of an ecologist to benefit pollinators, invertebrates and other wildlife.

Brown roofs are low maintenance, but left without attention they will be taken over by invasive weeds and deep-rooted species, that could damage the ecosystem and the waterproofing.

• Biannual or quarterly maintenance visits are recommended to: a) remove sapling trees and invasive shrubs such as Buddleia; b) clear unwanted weeds; and c) check the irrigation systems, gutters and drains.

See: Living roof maintenance for more information.

• How is a living roof constructed?
• How do you choose a living roof system, supplier and installer?
• What is the difference between a brown roof, blue roof and green roof?
• What are the benefits of a living roof?
• How do living roofs impact biodiversity?
• Do green roofs impact chances of getting planning permission?