Search results for "Cool roof"
showing 7 items of 7 documents
Computing methods for resilience: evaluating new building components in the frame of SECAPs
2019
Resilience represents a new important feature that the anthropic systems, and cities among them, are called to cope with. In fact, the increasing negative stresses to which urban contexts are exposed, and mainly the climatic pressures, call for the capability of adapting to these modifications and, possibly, to restore the ex-ante situations. The role of the buildings and their envelope components is of crucial importance to this aim. This paper analyses the features of resilience of the roofs of buildings by means of proper quantitative indexes. On purpose, the performances of green and cool roofs are compared. The possibility of adopting nonstructural solutions, like the windows shading d…
Comparing indoor performances of a building equipped with four different roof configurations in 65 Italian sites
2020
Abstract—Despite the increasing concern of institutions and technical organizations toward the improvement of the building energy (and, therefore, environmental) efficiency, the main goal of technicians should be also devoted toward the levels of internal thermal comfort that buildings are able to realize. As that, the relationships between energy performances and comfort conditions provided by the enclosures are of paramount importance in guiding designers in their work. In this paper, the influence of diverse roof construction typologies on energy and indoor performance of buildings has been investigated, in different Italian sites during heating and cooling seasons. In addition, it must …
Considerations about an indicator aimed at describing the energy efficiency of buildings with innovative envelope components at different climatic co…
2020
Green roofs are building components that have become increasingly common in urban contexts because other than the general improvement of the aesthetics of the buildings equipped with them, they have demonstrated to positively improve the building energy performance. Consequently, it would be useful for technicians to have easy and reliable indicators to achieve a synthetic quantitative judgement about the effectiveness of green roofs by an energy perspective compared to others building envelope technologies, for different climates. In sight of the definition of such an indicator, or at least of its properties, some considerations aimed at this purpose, especially concerning the use of new c…
Towards resilient cities: Advancements allowed by a multi-criteria optimization tool to face the new challenges of European Union’s climate and energ…
2019
Abstract The United Nations as well as the European Union are strongly committed in promoting a transition towards more sustainable and resilient cities. Indeed, they are increasingly affected by different types of threats, among which the natural ones such as earthquakes, fires, and floods (shocks) and climate variability (stresses). Cities are quite often unable to cope with the adverse effects of such natural hazards. This circumstance leads to the need of introducing resilience-related criteria (besides commonly used sustainability indicators) in decision-making processes. This paper investigates at which extent the inclusion of such new indicators, within multi-criteria assessment tool…
Green vs Traditional Roofs: Assessing their Actual Benefits through an Integrated Indicator Developed for Cool Roofs
2020
Green roofs have caught on in cities, mainly because contribute positively to thermal behaviour of buildings equipped with them. This paper investigates the applicability to these roofs of an integrated indicator, developed by Levinson and Akbari, to assess the contribution of cool roofs to buildings’ energy consumption. A building, assumed as the reference for the Italian medium size offices, was considered and its energy performance with and without the green roof was assessed. Different sites with different climatic conditions were considered for the simulations. First results indicate that such indicator does not seem to be completely transferable to green roofs.
Enhancing values of roofs albedo for lowering cities’ air temperature and electric demand of buildings: a simple economic evaluation
2019
Abstract In cities vegetated roofs are becoming more popular because they can mitigate Urban Heat Island phenomena by decreasing the outdoor air temperature in summer. This decrease reduces the electric energy demand for climatization of buildings, which, in front of a milder climate, will recur less to mechanical tools for guaranteeing thermal comfort conditions to occupants. Cities can registered another indirect positive effect: the reduced cooling energy demand, limits the heat released by the climatization systems’ external unities toward the urban open spaces, thus lowering the outdoor air temperature. Therefore, the outdoor surface temperature of green, as well as cool roofs, can be …
A simple methodology for comparing cost-benefit of traditional, green and cool roofs
2019
Energy policy makers, architects and researchers, when designing new buildings or rehabilitating the existing ones, are engaged in the attempt of limiting the energy needs for climatization (NZEB buildings) and the environmental pressure exerted by buildings (EU Climate Action). The pursuit of this demanding assignment calls for innovative solutions in conceiving the building envelope and its energy systems. Recently, among the most effective tools for improving the energy and environmental performances of buildings, the technical interventions regarding the roofs are gaining a rising attention. Indeed, covers of buildings are responsible of a relevant part of their energy losses and, on th…