Green Roof Planting Medium

It should also be light weight resistant to decomposition and compression and physically and chemically stable.

Green roof planting medium. Lightweight volcanic aggregate such as pumice or lava. The simplest most affordable and lowest maintenance green roofs comprise a carpet of sedums. The planting medium in extensive green roofs ranges from 1 6 to 6 inches deep and while deeper systems have been installed they are not favored as much as the shallower systems drought tolerant sedums succulent plants and grasses are the typical plants used since they are shallow rooted and use little water plant diversity on these roofs is kept low to simplify care and to be sure all plants have similar moisture requirements. Pumice is somewhat porous and is lighter than most aggregates.

With this type of roof planting mediums are much deeper which can be between seven and 24 inches and can consist of lawn shrubs trees and perennials for example. If you want your roof to function as a garden and have large plants and even water features then the intensive green roof is for you. This of course can be reflected in the cost of building materials. Types of green roofs.

Green roof substrate has been researched developed blended and improved over several decades. These aggregates make a good basis for a growing medium. The extensive green roof lightweight cost effective and. In general the bulk of the water storage in a green roof buildup is in the growing medium.

Careful consideration and planning is required during the design phase of a green roof build and a local growth expert should be consulted in order to develop the best system for your needs. It s a huge deal you don t see that often. For the best green roof medium the growing media should contain the following. Green roof growing medium green roof growing medium what s so special about it.

Weight is an. Green roof materials commonly referred to as growing media or soil substrates the growing medium used is an essential part of the green roof system. Over a 100m2 green roof with 10cm depth of growing medium the weight saved by using substrate instead of soil is considerable. What was really exciting about rooflite is that they were interested in developing a high quality media mix to suit farming.

These generally require a 5 15cm 2 6in depth of growing medium that can consist mainly of lightweight inorganic materials such as perlite leca sand rockwool and crushed tiles or concrete. These materials are available throughout the west coast of north america. Rooflite soil provides key features for excellent green roof performance. Roofs with a pitch of more than 20 degrees are best divided up into multiple boxes or compartments to stop the growing medium from simply slipping off or sloshing away in wet weather.

Slopes greater than 30 degrees are generally unsuitable for green roofs.