Extensive Green Roof Energy Savings

During representative periods of heating demand december and january the electrical energy consumption of rubber crumbs and pozzolana cubicles.

Extensive green roof energy savings.

In summer the green roof protects the building from direct. Shading the outer surface of the building envelope has been shown to be more effective than internal insulation. Therefore extensive green roofs especially with rubber crumbs as drainage layer can be a good tool for passive energy savings during summer periods in dry mediterranean continental climate. The green roof growing media green roof soil is the breathable layer.

1 2 in addition green roofs can reduce building energy use by 0 7 compared to conventional roofs reducing peak electricity demand and leading to an annual savings of 0 23 per square foot of the roof. Green roofs are energy efficient. A 2006 study by the university of michigan comparing costs of conventional and green roofs showed that on average installing a green roof costs about 22 00 sq. Whilst green roofs are important for cooling cities as a whole a green roof can roof can also have a positive impact on the energy balance within any given building this is particularly relevant if a building has poor insulation and poor ventilation.

There is only one difference. The green roof market is dominated by extensive designs with shallow growing mediums and deciduous plants that offer little potential for winter energy conservation. For a conventional roof. The energy saving potential wh m 2 is calculated by dividing the difference of cooling energy between the respective reference model and the model with an extensive green roof added by the.

Green roofs are often compared to white roofs which are only used to reduce the amount of heat entering a building or to reduce the urban heat island in the summer 3. One of these benefits is the potential for building energy savings where a green roof can reduce annual heating and cooling loads. The breathable layer growing media on a green roof is also the basis for the well being of the plants and must be able to store water and air at the same time for a healthy growth. Many studies have been conducted to assess the extent of energy savings possible with extensive green roofs.

Green roof temperatures can be 30 40 f lower than those of conventional roofs and can reduce city wide ambient temperatures by up to 5 f. There are many different reported benefits that the addition of a green roof to a building can offer. 8 to 20 per square foot. Energy performance is a key benefit of green roofs.