Energy saving of doors and windows, look here! The factors that affect the heat loss of doors and windows are disclosed.
In building energy saving, the role of doors and windows cannot be underestimated. To evaluate whether a building is energy-saving, it depends on whether it has saved resources to the maximum extent during the entire life cycle of the building, including energy saving, land saving, water saving, and material saving, whether it protects the environment and reduces pollution, whether it provides people with healthy and efficient use space, and whether it is a building that coexists harmoniously with nature.
Many factors affect the size of heat loss of doors and windows, mainly the following aspects:
1. Heat transfer coefficient of doors and windows
The heat transfer coefficient of doors and windows refers to the amount of heat transferred through a unit area per unit of time. The larger the heat transfer coefficient, the greater the heat loss through doors and windows in winter, and the more heat comes in from outside in summer. The heat transfer coefficient of doors and windows is related to the material and type of doors and windows.
2. Air tightness of doors and windows
The air tightness of doors and windows refers to the ability to prevent air infiltration when doors and windows are closed. The air tightness of doors and windows has a great impact on heat loss. Changes in outdoor wind force will hurt room temperature. The higher the air tightness, the less heat loss and the smaller the impact on room temperature.
3. Window-to-wall ratio coefficient and orientation
The window-to-wall ratio refers to the ratio of the area of the exterior window to the area of the exterior wall. Usually, the heat transfer resistance of doors and windows is much smaller than that of the wall. Therefore, the cold and heat consumption of the building increases with the increase in the window-to-wall area ratio. As a measure for building energy conservation, it is required to determine the appropriate window-to-wall ratio under the conditions of meeting lighting and ventilation.
Generally speaking, the solar radiation intensity and sunshine rate in different directions are different, and the solar radiation heat obtained by the windows is also different.
The main way to save energy for doors and windows is thermal insulation. The measures include: selecting energy-saving window types, improving the thermal insulation performance of doors and windows, improving the air tightness of doors and windows, and determining the appropriate window-to-wall ratio and orientation.
Under conditions where lighting and ventilation permit, controlling the window-to-wall ratio is more effective than setting up sunshades and window panels. That is, the smaller the window-to-wall area ratio is designed, the smaller the heat loss will be, and the better the energy-saving effect will be.