This paper analyses and compares the embodied and operational greenhouse gas (GHG) emissions of two nearly Zero Energy Buildings, a student housing building in Trondheim, Norway, and a residential building in Växjö, Sweden. The student housing in Trondheim, Moholt Allmenning Tower B, is a 9-storey tower composed of cross laminated timber (CLT) panels and concrete floor slabs with a total heated floor area of 3801 m². The apartment building in Växjö, House A, consists of 8 floors composed of glued laminated timber (glulam) beams with a wood-cassette floor, and concrete slabs with a total heated floor area of 3483 m². The results show that the use of CLT has the largest reduction of total GHG emissions due to substituting concrete elements in the structural frame. The comparative assessment of the external wall and the internal floor constructions shows that the use of CLT adds marginal GHG emissions per unit of area of component. The calculation of operational GHG emissions shows that the use of the Nordic electricity mix disfavours the full-electric energy system of Moholt Allmenning Tower B, in contrast to the district heating used in Norra Vallen Building A.

本文分析并比较了两个接近零能耗的建筑物，位于挪威特隆赫姆的学生宿舍楼和位于瑞典韦克舍的居民楼的实际和运营温室气体（GHG）排放。位于特隆赫姆的学生公寓，Moholt Allmenning塔B，是一栋9层的塔，由交叉层压木板（CLT）板和混凝土楼板组成，总加热地板面积为3801 m ²。Växjö的A楼公寓楼由8层组成，由胶合层压木（胶合木）梁和木盒式地板组成，混凝土板的总加热地板面积为3483 m ²。结果表明，由于在结构框架中替代了混凝土元素，因此使用CLT减少的温室气体总排放量最大。对外墙和内部地板结构的比较评估表明，使用CLT会增加单位面积的边际温室气体排放量。运营温室气体排放量的计算表明，与诺拉·瓦伦大楼A中使用的区域供热相比，北欧混合能源的使用不利于Moholt Allmenning塔B的全电能系统。