High Density Building Stock Retrofit through Solar Strategies and Hybrid Ventilation Systems

The very actual theme of building stock retrofit includes wide ranges of possible actions, especially in social housing. Multi-criteria assessments should be lead to evaluate the proper operational approach (considering social, structural, maintenance, thermal and economic parameters). The lower-impact actions typically involve improvements on the building skin, such as insulation and window re-placement, while the higher-impact solutions lead to demolition and re-building. Overall, building retrofit through solar technologies represents a relevant strategy to achieve significant energy saving. In this context two comparative solutions have been proposed for an early ‘80s social building in Modena. The former consists in the ap-plication of passive systems to optimise solar gains and active tech-nologies to generate energy. The latter is based on demolition and re-building of a newly designed block according to best practice princi-ples. The performance of solar strategies efficiency has been evaluated through parametric markers, while multizone thermodynamic and CFD analysis have been used to estimate the effects of passive cooling technologies.