Recently, there have been more and more questions about window soundproofing (the sound of window insulation will decrease when the temperature drops, and the sound insulation volume will be 4-5 decibels lower in winter than in summer), and popularize the basic knowledge of soundproof windows.
Talk about six aspects: single-glazed windows, insulating glass windows, laminated glass windows, laminated + insulating glass windows, double-layer windows, and 4SG glass windows (the so-called full-frequency noise reduction windows).
Any form of window follows the sound insulation rules shown in Figure 1, and there are sound insulation defects caused by low-frequency resonance frequencies (red circles) and high-frequency anastomosis (yellow circles), and any improvements are made to improve the sound insulation volume and avoid these two soundproofing defects.
1. Single-glazed windows - Figure 2
Effect: The sound insulation effect of high and low frequency is poor.
Characteristics: The single-layer glass has not been improved in any way, and the sound insulation defects of high frequency and low frequency are obvious, and the sound insulation is obviously insufficient.
The sound insulation defects of single-layer glass are located at about 150 Hz (at the resonant frequency) and around 2000 Hz (at the anastomotic frequency), as shown in Figure 2.
2. Insulating glass windows - Fig
Effect: Poor sound insulation at low frequencies, good sound insulation at medium and high frequencies.
Characteristics: Because of the hollow layer, the insulating glass has a good sound insulation effect on medium and high frequency noise, but it still has low frequency sound insulation defects.
The sound insulation defect of the insulating glass is located at about 300 Hz (at the resonant frequency), and the sound insulation defect of the high-frequency anastomosis frequency is not obvious, as shown in Figure 3 (same as 2).
In addition, when the cavity width of the insulating glass reaches 80 mm or more, the problem of low-frequency sound insulation defects can be solved, as shown in Figure 4 (the resonance frequency is moved down to less than 100 Hz, and the sound insulation is basically not affected).
3. Laminated glass windows - fig. 5
Effect: The sound insulation of medium and low frequencies is better, and the sound insulation of high frequencies is not improved much.
Characteristics: Laminated glass is a two-layer glass sandwich damping layer, due to the existence of the damping layer, the sound insulation defects at the resonance frequency can be improved, the sound insulation effect of the middle and low frequency is better, but the damping layer has less improvement on the anastomosis effect, so its high-frequency sound insulation is slightly worse, as shown in Figure 5.
In addition, the temperature has a great influence on the laminated glass, and the sound insulation decreases significantly in winter.
Fourth, laminated + hollow - Figure 6
Effect: High and low frequency sound insulation is better.
Features: Laminated + hollow window, integrating the advantages of insulating glass and laminated glass, avoiding the sound insulation defects of low-frequency resonance frequency and high-frequency matching frequency, as shown in the black curve in Figure 6 (blue is insulating glass).
5. Double windows - Figure 7
Effect: Combined with the advantages of lamination, hollow and large cavity, the sound insulation effect is the best.
Characteristics: hollow and laminated only to improve the sound insulation defects as much as possible, and the double-layer window can avoid the appearance of sound insulation defects, and the sound insulation is the best, as shown in Figure 7 (Figure 7 up and down are hollow + laminated and double-layer window sound insulation respectively), the principle can also refer to the large spacing cavity insulating glass in Figure 4.
VI 4SG glass windows.
Effect: **The highest, the sound insulation effect is very good, and the heat preservation, life and so on are the best.
Characteristics: The appearance of resonance frequency is due to the boundary constraint, the boundary constraint of 4SG glass window is soft, and the unequal cavity technology is adopted, the sound insulation defect is not obvious, and the sound insulation effect is good.
Limited number of words, simple summary.