1. Question: What’s external sunshade?
Answer: In a broad sense, the sunshade system refers to indoor and outdoor sunshade system. It consists of external sunshade and internal sunshade according to the location of installation.
2. Question: What types do external sunshade and internal sunshade have?
Answer: External sunshade includes common sunshade board, awning, aluminum roller shutter window, sunshade blinds, etc. The internal sunshade includes common roller shutter, venetian blinds, Roman blinds, cloth curtain, etc.
3. What’s the difference between the external sunshade and the internal sunshade?
Answer: When we use internal sunshade (blinds, curtains, etc.), only part of solar radiation can be kept out. Due to the infrared ray from the sun heating the glass, visible and ultraviolet light makes the sunshade material’s temperature rise, so that the air temperature between internal sunshade and the window rises accordingly. However, the external sunshade can keep out the solar radiation before it reaches your window. In addition, the flowing air between the external sunshade and window can take the heat away, so that the heat will not enter your room, neither heat your window. Therefore, your room will be as cool as the shade of trees. That is why the effect of external sunshade is far more effective than that of internal sunshade.
4. What’s the advantage of external sunshade roller shutters?
Answer: External sunshade roller shutters are the effective sunshade measure applicable to windows facing each direction. When the shutter is fully put down, it can block out almost all the solar radiation. Therefore, the heat absorbed by the external window contains only the part that solar radiation energy transfers to the interior.
5. Why do external sunshade roller shutters have better energy-saving effect and be more economical?
Answer: The sun has three main wavebands: infrared, visible light, and ultraviolet light. When light shines onto the window glass, the infrared is absorbed by glass. The radiant energy is converted into heat, so the windows warm up. The visible light and ultraviolet light that pass through the glass and enter the room are absorbed by indoor objects. The indoor objects that absorb radiant energy convert it into heat, so that the temperature of the whole house rises. The internal sunshade (blinds, curtains, etc.) can only keep out partial sunshine, so the high-energy ultraviolet radiation will make the temperature of the window rise. Then the high-energy ultraviolet radiation enters the room and makes the temperature of sunshade materials rise, so that the air temperature between the internal sunshade and the window continuously rises accordingly. These three parts (window glass, internal sunshade material, and the air layer between the two) work like radiators to continuously heat your house. However, external roller blind window has a big difference from it. It can block the sun outside of your windows in the first time. Since roller shutters are installed outside the house, the constant flow of air above can bring away the heat at any time, so that the heat will not have the slightest opportunity to enter your house and the sun will not shine onto your window either. Therefore, the three heat sources (window glass, internal sunshade device, and air layer between the two) that will heat the house are kept out. In this sense, the energy saving effect of external roller shutter is much better than that of internal sunshade. In Shanghai, the energy-saving rate of external roller shutter in the summer can reach 45%, so it has a better effect than that of wall insulation board.