Green Roofs

In order to install a green roof you need a structurally sound roof, that will hold the added weight, which can be pretty excessive when you factor in the soil and vegetation. The costs of installing a green roof are about $10-20 more per square foot than a normal roof. Already existing roofs are usually not designed to withstand the added weight so a retrofit can be impractical. The maintenance costs can be pretty high as well. Some alternatives to a green roof would be a garden or even a "bio-wall".

If you're in a position where you can install a green roof, they can be very beneficial to the environment and can play a substantial role in decreasing the "heat island effect". A green roof reduces storm water runoff and absorb pollutants. They are also added garden space, that will allow the owner to grow many different varieties of plants. Depending on the type you can even grow small trees. Green roofs can be categorized into 3 different types which include "intensive", "semi-intensive" or "extensive". Intensive green roofs require labor intensive maintenance. The soil depth is greater than extensive green roofs and they can hold larger medium or large plants. An extensive green roof is usually self sustaining and lightweight. They are usually not meant to hold the weight of people or larger plants. Semi-intensive green roofs are a combination of extensive and intensive green roofs. The can hold a wider range of plants than an extensive green roof, cost less in maintenance than an intensive green roof and in some cases are A.D.A compliant and can hold the weight of people.