Research on Energy Efficiency Design Key Parameters of Envelope for Nearly Zero Energy Buildings in Cold Area

The insulation thickness of envelope, heat transfer coefficient of window and ratio window to wall are the main factors that affect the building energy consumption in cold area. The demonstration building model is established through DEST energy consumption simulation software. Multiple factors with single variable method is used to study the performance parameters of building envelope and establish the energy efficiency design key parameters of nearly zero energy buildings. According to the calculating result, the value of heat transfer coefficient for exterior wall is 0.096 W / (m2
- K). The value of heat transfer coefficient for outer window is 0.780 W / (m2
- K). The value of solar heat gain coefficient SHGC value is not less than 0.474. Based on these selections above envelops, the ratio window to wall is 0.15-0.25 in south facades. The energy consumption is increased linearly with the rise of ratio window to wall in other facades.