Green Roof Heat Loss

This energy is known as latent heat.

Green roof heat loss.

Informational signs can accompany green roofs to educate building occupants and visitors to the benefits of the green roof and how to protect the resource. A green roof system is an extension of the existing roof which involves at a minimum high quality water proofing root repellent system drainage system filter cloth a lightweight growing medium and plants. A green roof can also provide a refuge for insects and birds that have lost their natural habitat due to urban development and the loss of green space. The allegheny county office building green roof was found to lose 8 2 less heat than the control roof in heating months and gain 75.

Green roofs improve and reduce energy consumption. They can reduce heating by adding mass and thermal resistance value also can reduce the heat island by increasing evapotranspiration. It is clearly seen that the heat loss from the green roof is notably greater than the building having no green vegetation on the roof. The heat transfer through the walls and roof during heating season can be viewed in fig.

The heat loss through the roof without green vegetation is determined to be 0 388 gj for scenario 1 and 3. Energy conservation translates into fewer greenhouse gas emissions. A green roof or rooftop garden is a vegetative layer grown on a rooftop. The hamerschlag hall green roof was found to lose 26 less heat than the control roof in heating months.

A 2005 study by brad bass of the university of toronto showed that green roofs can also reduce heat loss and energy consumption in winter conditions. This roof type can be much more expensive to implement than other efficient roof options so you should carefully assess your property and consult a professional before deciding to install a green roof. The main findings of the study were that green roofs are able to reduce the indoor temperature of buildings and are able to achieve better heat transfer through the roof and thus a lower cooling. Because green roofs store water in the growing media and plants latent heat loss is accomplished via transpiration from plants and evaporation of moisture from the growing medium collectively referred to as evapo transpiration.

Green roofs improve air quality. Green roofs have been proven to help reduce heat islands. In winter the green roof minimizes heat loss through added insulation on the roof. The effect that the green roof media has on the thermal performance of the roof system was evaluated.

As roofs are the site of the greatest heat loss in the winter and the hottest temperatures in the summer. Green roofs also provide insulation lower the need for heating and cooling and can reduce the urban heat island effect.