Energy-saving renovation methods for windows

Improving the energy efficiency of doors and windows primarily involves enhancing their thermal insulation properties. In cold regions in the north, energy efficiency focuses on heat preservation, while in hot summers and warm winters in the south, emphasis is on heat insulation. Regions with hot summers and cold winters need to balance both heat preservation and heat insulation. Several aspects can be considered to enhance the thermal insulation of doors and windows:

First, strengthening heat insulation:
The focus here is on existing buildings in the southern regions of China, such as hot summer and cold winter regions and hot summer and warm winter regions. The thermal insulation performance of windows and doors mainly refers to the ability of windows and doors to block the solar radiation heat into the room in summer. The main factors affecting the thermal insulation performance of doors and windows are the thermal and photophysical properties of the door and window materials, inlay materials (usually referred to as glass), and so on.
The smaller the thermal conductivity of the door and window frame materials, the smaller the conductivity of the doors and windows. For windows, the use of a variety of special heat-reflective glass or heat-reflective film has a very good effect, especially the selection of infrared reflection of sunlight in the ability to reflect the reflection of the material is more ideal, such as low-e glass. However, in the selection of these materials should take into account the light of the window, can not be loss of light transmission of the window to improve the thermal insulation performance, otherwise its energy-saving effect will be counterproductive.

Second,strengthen the window inside and outside the sun shading measures：
Under the premise of meeting the design requirements of the inside of the building, the addition of external sunshade panels, awnings and the appropriate increase in the length of the south-facing balcony pick out can have a certain shading effect. Heat-reflecting fabric curtains coated with metal film are installed on the inside of the windows, which have a decorative effect on the front side and form a less mobile space air layer of about 50mm thick between the glass and the curtains. In this way, a good heat-reflecting insulation effect can be achieved, but the direct lighting is poor and should be made movable. In addition, the installation of blinds on the inside of the window has a certain heat-reflecting effect, can also obtain a certain degree of thermal insulation.

Third,improve the thermal insulation performance of windows and doors
Improving the thermal insulation performance of external doors and windows of buildings mainly refers to improving the thermal resistance of doors and windows. As the thermal resistance of single-layer glass windows is very small, the temperature difference between the inner and outer surfaces is only 0.4 ℃, therefore, the thermal insulation performance of single-layer windows is very poor. The use of double or multi-layer glass windows, insulating glass, the use of air between layers of thermal resistance, can significantly improve the thermal insulation performance of the window. In addition, the selection of thermal conductivity of small door and window frame materials, such as plastic, broken heat-treated metal frame material, etc., can improve the thermal insulation performance of external doors and windows. Generally speaking, the improvement of this performance also improves the thermal insulation performance at the same time.

Fourth,improve the airtightness of windows and doors
Improve the airtightness of doors and windows can reduce the energy consumption generated by the heat exchange. At present, the airtightness of the building's external doors and windows is poor, and its airtightness should be improved from the production, installation and addition of sealing materials for doors and windows. In the design, the determination of this indicator can be based on the amount of hygienic air exchange 1.5 times / h to consider, that is, it does not necessarily require doors and windows absolutely airtight. For buildings in the northern region, to enhance the airtightness of windows and doors to reduce the impact of winter heating energy consumption is very large.