Roof garden benefits
Storm Water Management: green roofs help alleviate storm water runoff through retention and detention of the rainwater. This benefit can cut costs associated with required municipal on-site storm water retention
Air and Water Purification: roof gardens help to purify the air by converting CO2 into oxygen, helping to reduce greenhouse gases. The roof garden soil structure helps to purify the water through filtration and can be designed to provide a method for neutralizing acid rain
Provides Sound Insulation: the growth media, plants and layers of trapped air in a green roof system serve as excellent sound insulators. Tests have shown that green roofs can reduce indoor noise pollution caused by outdoor contributors
Extends Roof Life: roof gardens can protect roof membranes from ultraviolet radiation, extreme temperature fluctuations and puncture or other physical damage. Minimization of such exposure can improve the long term performance of the roofing system.
Adds Value Aesthetics: green roofs can provide the urban environment with visually pleasing vistas and rooftop gardens. In urban environments, Roof gardens also add value by converting space into areas usable for recreation by the occupants. In such locations, the scarcity of real estate makes the addition of a roof garden for such recreation a competitive alternative
Ultra-Extensive (shallow) Roof Garden System: a shallow planting system (from 6 to 10 cm in depth) ideally suited for areas that will receive little maintenance. Recommended plants include sedums, herbs and grasses. The anticipated weight above the membrane assembly is generally between 5 and 8 pounds per square foot, per inch of system depth, in a saturated state
Extensive (medium depth) Roof Garden System: a medium depth planting system (from 10 to 20 cm in depth) where recommended plants include sedums, herbs, grasses and other vegetation which can grow in this depth of media. In temperate climates, un-irrigated systems can be provided without difficulty. However, drip, mist or spray irrigation systems may be
required to support more diverse plant types or for installations in semi-arid climates. The anticipated weight above the membrane assembly is generally less than 50 pounds per square foot
Intensive (deep) Roof Garden System: a planting system of greater depth (soil depth greater than 20 cm) that requires regular maintenance, such as watering, fertilizing and mowing/weeding. A variety of plants are available including sod grass, annual or perennial flowers, shrubs and even small trees. This system typically requires a structural concrete roof deck to support the larger dead load. An irrigation system may be utilized in these assemblies, as required.