NATS Nursery Ltd. - Native Plants

  • Vancouver Convention Centre Roof

    North America’s largest non-industrial green roof

Green Roofs

What is a green roof?
A green roof, or vegetative roof, is a conventional roof that has been enhanced with a waterproof membrane, a drainage system and a growing medium which is then covered in vegetation. Like any planted area, green roofs experience periods of growth, flowering and dormancy, and so they are sometimes referred to as living roofs. Green roof installation is on the rise thanks to well documented economic, social and environmental benefits, but they are not a new phenomenon as some of the earliest documented green roofs date back to the sod roofs found in Scandinavia during the Viking and Middle Ages.

Why install a green roof?
Green roofs offer an wide range of economic, environmental and social benefits. The most commonly cited are: stormwater mitigation, reduction of the Urban Heat Island Effect, thermal efficiency, energy conservation, noise reduction, aesthetics, improved air quality, and increased biodiversity. To find out more about the benefits of a green roof, visit Green Roofs for Healthy Cities.

What is the difference between extensive and intensive green roofs?
An extensive green roof uses a thin (8cm to 20cm) layer of substrate to create a carpet of plants, often sedums and grasses. Extensive green roofs often occur on structures that cannot support more than just shallow substrates, and so these roofs are only minimally accessible to people.

An intensive green roof can support much greater depths of substrate, and therefore much larger plants. Depending on the building’s structural capacity, an intensive green roof can support features that might be found in ground-level gardens, like trees and stone garden planters. These areas tend to be designed for public use.

How do green roofs fit into LEED certification?
The Leadership in Energy and Environmental Design (LEED) Green Building Rating SystemTM is an internationally accepted benchmark for the design, construction, and operation of high performance green buildings. Green roofs can contribute as many as 15 points towards a building’s LEED rating.

Find Out What Type of Green Roof is Right for You