Passive Cooling Roof Design

Engineers worked to change the concept of roof cooling from a ponding to an evaporative technique.

Passive cooling roof design.

Passive cooling is a building design approach that focuses on heat gain control and heat dissipation in a building in order to improve the indoor thermal comfort with low or no energy consumption. These are the two main categories of passive cooling. Researchers have developed a numerical model that was able to verify the effects on passive cooling of buildings caused by the density variation of vegetation of green roofs. Passive cooling is free unlike air conditioning which is expensive to install and run.

Passive solar design refers to the use of the sun s energy for the heating and cooling of living spaces by exposure to the sun. Well designed building envelopes minimise unwanted heat gain and loss. Depending on your situation climate house style personal preferences etc it is most effective if you incorporate the principles of both passive cooling and passive heating. Cool roofs a cool roof is one that has been designed to reflect more sunlight and absorb less heat than a standard roof.

This is a simple building integrated cooling scheme that uses nighttime radiation cooling from a metal roof to cool air in the attic space. Designing the floor plan and building form to respond to local climate and site. This cooling reverses the heat flow through the roof. Passive design utilises natural sources of heating and cooling such as the sun and cooling breezes.

Attic air is then circulated into the living area to provide cooling. This approach works either by preventing heat from entering the interior or by removing heat from the building. With just an error. It is achieved by appropriately orientating your building on its site and carefully designing the building envelope roof walls windows and floors of a home.

Heat is now transferred out of the building through the roof. Natural cooling utilizes on site energy available from the natural environment combined with the architectural design of building components rather than mechanical systems to dissipate hea. Passive cooling design principles. When sunlight strikes a building the building materials can reflect transmit or absorb the solar radiation.

To achieve thermal comfort in cooling applications building envelopes are designed to minimise daytime heat gain maximise night time heat loss and encourage cool breeze access when available. Modulation is a technique used to transfer the heat via thermal mass or natural cooling dispersing it at a later time or when needed. How roof cooling works. An evaporative roof cooling system is designed to reduce the temperature of a roof from 165 f to about 90 f.

Passive cooling should be part of an overall approach to passive design.