Roof cooling techniques

Roof cooling techniques can help exploit ambient heat sinks selectively so as to contribute further, or more directly, to the cooling of buildings. Two recent European projects have investigated a series of possible applications suited to Mediterranean climates and building typologies, and the results form the basis of a handbook on Roof Cooling Techniques. Following experimental measurements on test cells in Spain, Greece and Israel a dynamic model was developed and applied to parametric studies investigating a range of roof cooling techniques combining radiative and evaporative cooling processes: variants of roof ponds, water-based and air-based radiators. The parametric studies were extended to produce comparative applicability maps and guidelines. These give a measure of likely cooling energy savings compared to air conditioning and likely thermal comfort improvements for free-running residential buildings. The paper will present the main findings and design guidelines produced by the parametric studies.