Weighting is an important step that supports comparison and decision-making in the LCA (Life Cycle Assessment) of buildings. However, temporal variations of weighting systems have not been adequately studied. Given the increasing demand of addressing time issues in LCA, this study attempts to develop a dynamic weighting system. Three common weighting approaches—expert panel, monetization, and DTT (distance-to-target)—are compared, and the DTT approach is selected for utilization. Temporal variations of emission targets and resource characteristics are considered in the new weighting system, which includes short-term, medium-term, and long-term weighting factors. The dynamic weighting system makes it possible to quantify environmental impacts with temporal-varying environmental policies and planning, and the assessment results could better guide design improvements with various environmental priorities in different periods considered. A residential building is taken as case to test the operability of the new weighting system. The significant difference between the assessment results weighted by the traditional versus the dynamic weighting systems indicates the necessity of considering temporal variations.

加权是支持建筑物LCA（生命周期评估）中比较和决策的重要步骤。但是，加权系统的时间变化尚未得到充分研究。考虑到LCA中解决时间问题的需求不断增加，本研究尝试开发动态加权系统。比较了三种常见的加权方法-专家组，货币化和DTT（到目标的距离），并选择了DTT方法进行利用。新的加权系统考虑了排放目标和资源特征的时间变化，其中包括短期，中期和长期加权因子。动态加权系统可以通过随时间变化的环境政策和规划来量化环境影响，评估结果可以更好地指导在不同时期考虑各种环境优先事项的设计改进。以一栋住宅楼为例，测试新加权系统的可操作性。传统评估系统与动态评估系统加权的评估结果之间存在显着差异，表明有必要考虑时间变化。