The location of doors and windows were divided into their envelope components or separating elements have different design requirements to be separately with insulation, heat insulation, sound insulation, waterproof, fire and other functions, the new energy-saving requirements, cold regions from the doors and windows gap the heat loss, the total heating about 25% of heat consumption. Closed doors of the requirements is an important energy-saving design. Doors and windows of the building envelope system is an important component. The role of the two: doors and windows is an important part of architectural style (the actual situation contrast, rhythm artistic effect, plays an important role) so that their shape, size, proportion, arrangement, color, shape, etc. The overall shape of the building have a great impact. www.beixinjianshe.com