Meta-Design Approach to Environmental Building Programming for Passive Cooling of Buildings

Sustainable design practices are being disseminated all around the world, thanks to a growing interest by users, builders, and politicians in facing the impact of climate changes and the need for a more sustainable future. Nevertheless, although design practices include currently green issues and technologies, these are applied mainly in the last design phases in order to comply with local and/or national regulations and requirements (e.g. minimum values for the energy demand to be covered by renewable sources and for the envelope transmittance). Instead, to integrate sustainable technologies in an energy- and cost-effective way, it is necessary to deal with them since the earliest design phases, i.e. building programming and site analysis. Furthermore, passive and hybrid technical building systems (TBS) are dependent on the specific project context, and this is even more apparent for cooling. In fact, while the performance of passive heating TBS is mainly related to solar access and reduction of energy losses, the one of space cooling TBS depends on other variables such as internal heat gains, heat capacity, and wind environment. The paper describes a methodology to assess the energy- saving potential of passive ventilative systems in the earliest design phases. Site and climate aspects, together with definitions of needs and requirements for building programming, will be described. Results from an application of a method based on Givoni-Milne bioclimatic chart to evaluate the climate-dependent potential of passive system are reported. Criteria for spatial and technological integration of passive cooling systems are also presented.