How Thick Is A Green Roof

The nominal thickness of a green roof is the approximate total height of the soil and drainage components that constitute the green roof system excluding the roof structure insulation waterproofing and plants it is common practice to use the term extensive to describe green roofs that are very thin and will only support hardy drought resistant vegetation.

How thick is a green roof.

Butyl rubber membranes only should be used in conjunction with adhesives and tapes recommended by the membrane manufacturer. It is recommended that minimum 90 mil 2 3 mm thick reinforced butyl rubber membranes be used for green roof assemblies. The modern green roof movement began in germany in the mid 1970s. Our permaseal 20p membrane functions as both a drainage layer and as a reservoir see image above.

Intensive roofs which are thicker with a minimum depth of 12 8 cm 5 1 16 in and can support a wider variety of plants but are heavier and require more maintenance and extensive roofs which are shallow ranging in depth from 2 cm 13 16 in to 12 7 cm 5 in lighter than intensive green roofs and require minimal maintenance. Green roofs are also known as vegetative or eco roofs. The green roof drainage layer thickness depends on your needs. Do not install butyl rubber waterproofing membranes when ambient temperatures are below 40 f.

First you need to install a waterproof membrane that possesses monolithic properties. Although there are no precise definitions of them an extensive green roof has a shallow growing medium usually less than six inches with a modest roof load limited plant diversity minimal watering requirements and is often not accessible. The capacity of these dimpled membranes vary depending on your green roof requirements. An extensive green roof or sedum roof is a roof with vegetation that is more or less self perpetuating and that can further develop and maintain itself.

Building a green roof. At permagard we stock an 8mm and 20mm cavity. Roughly speaking extensive green roofs have a substrate thickness of between 4 and 15 cm and a weight of 30 to 220 kilo per m2. Its proponents were interested in creating green space in otherwise barren urban areas.

There are two types of green roof. How to construct a green roof. Here are some easy to follow guidelines for the construction or installation of a green roof.