Benefits

Aesthetics

Studies have shown that surrounding oneself with nature can be a form of psychological therapy with effects such as lowered levels of stress, blood pressure, muscle tension, and a substantial increase in positive feelings. This is especially relevant to areas of high-density living, such as an urban metropolis, where concrete and unattractive exteriors are seen more readily than vegetated surfaces. Green roofing can help to change this. Even smaller, residential areas can be improved by the implementation of beautiful gardens, and, where roofs are inaccessible, beautiful planting can be a delight to view.

Economics

While a green roof costs around 20% more than conventional roofing, roofing with vegetative covers offer an increased roof life of up to 20 to 50 years longer. Green roofing reduces heat exposure to a surface, consequently reducing the aging process of the conventional bituminous materials. Additionally, green roofs help to reduce heat transfer into a building, thus driving down cooling costs. When compared to conventional methods of roofing, indoor temperatures are typically 3 - 4 °C cooler. In some areas this has brought a reduction of up to 25% in summer cooling requirements. Today, both at home and abroad, many governmental organizations are beginning to award benefits to anyone taking an active part in the green building movement.

Environmental

Green roofing reduces storm water runoff. As falling water comes into contact with a conventional roof, it is not absorbed and escapes into drainage systems and rivers. Roofing with vegetated covers allows most of the water to be absorbed by the soil and eventually join the water table through evaporation. This helps to reduce flooding in urban areas, sewage overflow, and the overloading of wastewater treatment systems, which can cause the discharge of raw sewage into rivers. Green roofing also helps to reduce air pollution by filtering out fine airborne particles as the air passes over the plants. This can also help to reduce the overall temperature of a large area, such as an urban city, when green roofs are used extensively. Green roofing is a helping hand in increasing biodiversity of both plants and animals in the surrounding area and could prove to be very valuable in conserving or restoring endangered habitats and vegetation types.