HEROTILE - High Energy savings in building cooling by ROof TILEs shape optimization toward a better above sheathing ventilation

In Mediterranean regions the solar radiation in summer cause an overheating of the building envelope (roof and walls) and then of the indoor and the need for air-conditioning. Passive systems to limit solar effect mainly consist of ventilated facades and roofs. Roof is the most exposed element to solar radiation and this causes excessive heating of the attic and other rooms. Vented roof is capable to provide a discrete benefit for the disposal of heat due to solar radiation, but its performances are highly dependent on roof exposure and especially to its perpendicular direction to the wind. The benefit of the so-called Above Sheathing Ventilation significantly decreases when the wind direction shifts from perpendicular to parallel to eaves line.
ASV affects positively the thermal insulation thanks to convective heat transfer. Natural component linked to buoyancy-driven forces becomes irrelevant even with a very weak wind, while the air permeability of tiles determine an increase of the performances. Thus, vented tiled roofs could be considered the best solution for passive thermal building insulation in hot and mild climates.
Main objectives of the proposal are:
• realize two pilot plants to produce two new types of roof tiles with a shape characterized by a higherair permeability through the overlap of the tiles, and then a better energy performances by passive disposal of the solar radiation through under-tile ventilation. Two types of roof tiles covering more than 60% of pitched roofs in Europe (Marseillaise and Portuguese tiles) will be re-design with a new shape that allows air to enter through the overlap of the tiles, with the same level of waterproofing. The air inlet though the tile overlap greatly increases the amount of air and therefore a greater passive heat disposal, but above all it is independent from wind direction since the inlet and outlet lines are no longer eaves and ridge lines but the entire roof;
• two real scale test buildings, with seven different roofs each, will be made to test new tile performances in two different location (one outside EU) and two demonstrator buildings located in Mediterranean regions have been chosen to test and quantify benefits of new tiles;
• on the basis of experimental data, will be realize in addition a practical and simplified software for architects and technicians, able to predict the energy performance of the same building in changing only the roof configuration. The software will be free-license

June 2020: the project has been selected as finalist in the "Life 2020 Awards", section Climate Action. With this award, LIFE recognises the most innovative, inspirational and effective LIFE projects in three categories: climate action, environment and nature protection.

Notizie (in italiano)

• La tegola "salva energia" | Unife in finale per il premio europeo LIFE Awards