In the cost parameter, the cost of each strategy was obtained through the pricelist of the Camera di Commercio di Milano [44]. The cost of the maintenance material as well as replacement considered the average inflation in the last ten years in Italy, which is 1,34% a year [44].
                    Computer simulation
                    In order to assess the energy demand and the indoor comfort conditions of the building the EnergyPlus computer programme, version 8.4, was used. The building was evaluated considering the constant use and occupation for the users. Details on occupation, thermal load and use pattern were taken based on the Italian regulation for energy efficiency in buildings [45]. Equipment and lighting operated with 100% load during the operational hours. The building was evaluated in two different conditions: (i) while the naturally ventilated and (ii) operating with an air-conditioning system. The apartments while natural ventilated was analysed considering 20°C as the indoor temperature control of the opening or closing of windows. When the house was operating with air-conditioning, the operation period of artificial conditioning system was developed according to the indoor occupation of the house (bedrooms and living room). When users are not at home, the rooms are naturally ventilated and the indoor temperature adopted to control the opening or closing of windows was 20°C. In order to obtain the energy consumption for air-conditioning, the set-point temperatures were taken as 20°C for heating and 26°C for cooling [46].   Climatic data and tool to assess climate change   The effect of climate change in the case study was analysed. Recent studies show the importance to evaluate the effect of climate change in buildings [47, 48, 49]. For this reason, to analyse the design strategies through the four parameters, the effects of climate change on the building were studied. The tool Climate Change World Weather file Generator [50] was used for the A2 (medium high) emissions scenario for three future time slices, the 2020s, 2050s and 2080s [51]. The building was evaluated under the current climate data and in the three future climate data generated for the city of Milan using the weather data file in Test Reference Year (TRY) format. Recent studies explain with more details the operation of this tool [48, 49].
                        Fig. 7 shows the annual air temperature, relative humidity and global horizontal radiation in Milan in the four climate data files: current, 2020, 2050 and 2080.