People look at a mock up showing the insulated wall structure of the passive house under construction in Vancouver, Canada, Nov. 8, 2016. City of Vancouver led a tour to a six-storey, 85-unit residential building, which is constructed under the Passive Housing standard, which can reduce 80% of energy used compared to conventional buildings. This green building will be completed in spring 2017 and will become Canada's largest passive house. (Xinhua/Liang Sen)
