The Impact of External Insulation System Optimization on Building Life Cycle Energy Consumption

In order to determine the optimal parameters of the external insulation system and guide the building energy saving,this study chose a typical student dormitory in Beijing as research object.Life cycle assessment(LCA)and dynamic simulation method were used to research the relationship between the expandable polystyrene(EPS)external insulation system design parameters and the building energy consumption of materials production phase,operation phase,disposal phase and the whole life cycle.The results show:the consumption of clay brick,concrete and cement mortar account for 98.1% of the total materials consumption,where concrete contributes most to energy consumption(36.6%).Regarding the contribution to building life cycle energy consumption,materials production phase accounts for 5.6%~18.8%,building operation phase takes up 80.6%~93.4%,and the disposal phase can be neglected.With the increase of EPS insulation thickness,energy consumption increases linearly in the material production phase,decreases in building operation phase,and has an optimization value in the building life cycle,which will reach the minimum when the heat transfer coefficient(K)is 0.3 W/m2 K and the EPS insulation thickness is 130 mm.