The outdoor air temperature will increase over the years in Milan. Thus, by 2080, the annual mean outdoor air temperature will increase 3.6 °C compared to the current temperature. Instead, the mean relative humidity will decrease over the years. Thus, by 2080, the annual mean relative humidity will decrease 5.7% compared to the current climate conditions. Finally, the mean global horizontal radiation will increase over the years. Thus, by 2080, the annual mean global horizontal radiation will increase 7.2 Wh/m2, compared to the current global horizontal radiation. The analysis of the future climate condition in Milan shows the effect of climate change in the future. These climatic changes directly affect the energy and thermal performance of buildings, as demonstrated by recent international studies [47–49]. For this reason is crucial to consider the climate change effects when analysing the life cycle of buildings.
Results of the design strategies 
Fig. 8 shows the six design strategies analysed, through the four sustainable parameters, in the building.The Case 1 represent the design strategy used in the actual project of the building. The results show a different behaviour of the six design solutions. In the comfort parameter, the Case 4, reinforced concrete frame with rectified bricks, obtained the best result with more than 6000 indoor comfort hours, while the Case 5, steel frame and drywall with rock wool, has obtained lass than 5000 hours.   In the energy demand factor, the best design solution is the Case 3, reinforced concrete frame with cellular concrete blocks, with 1500 MWh, while the Case 2, X-Lam and wood fiber, obtained the worst result with 3400 MWh in the life cycle. In all design strategies the embodied energy represents the largest part of the energy consumed in the life cycle. In the Case 4 the embodied energy represent 91% of the total energy. The maintenance phase is also a relevant stage in the energy life cycle of the design strategies, accounting for 30% of total energy in the Case 5. In all design solutions, the demolition phase represents less than 2% of the energy consumed over the life cycle. Besides, Fig. 8 shows that the use of different databases (indicated through a line with the highest and lowest values) may influence the results of the life cycle to 30%. All this shows that the choice of the correct data-base is one of the main issues in a LCA study, as demonstrated by international studies [8, 10].  The results of the carbon dioxide emissions show that the two design solution in X-Lam frame are the best choices, with little more than 230 tCO2e. The Case 4, reinforced concrete frame with rectified bricks, obtained the highest emissions with 230 tCO2e in the life cycle. The embodied emissions represent the main part of the total emissions. The maintenance phase characterizes 34% of the life cycle emissions in the X-Lam structures, between 20% and 23% in the steel frame design solutions and only 8% in the reinforced concrete frame cases. The deconstruction phase represents around 3% of the design solutions life cycle. Even in the emission parameter, the variation of the results due to the three data-bases used is significant. In the entire life cycle of the X-Lam design solutions the result may vary by 200%.  In the cost factor, the best design solution was the Case 4, reinforced concrete frame with rectified bricks, with a cost of € 2,500,000, while the Case 2, X-Lam and wood fiber, obtained the worst result with a cost of € 2,927,000 in the life cycle. In all design solutions, the initial phase represents between 43% and 49% of the final cost, while the maintenance phase represents between 46% and 54% of the life cycle cost. The deconstruction phase represents between 1% and 5% of the final cost. An interesting fact concerns the cost of labour, which, unlike the energy and emission parameters, represents 40% of the cost of the life cycle.