If you live in a built-up area, near a busy road or railway line, it’s likely that external noise will have become a bit of a nuisance over time. One of the best ways to block out noise pollution is by introducing double glazing to your property. But how does double-glazing help to keep out the noise? And why is some double glazing better than others? This article goes into how double-glazing works to reduce noise and what to look for when buying double-glazing for that purpose.
How sound travels
To understand how sound insulation works, it’s important to first understand how sound enters your home in the first place. Sound is transmitted through sound waves, tiny vibrations, which pass from the source of the sound to our ears. In order for the sound waves to reach our ears, it requires material to pass through, one of which is the glass and surrounding structure of your windows.
How windows reduce sound
Sound travels more quickly through solid materials and liquids than through gases, and the denser the gas, the more difficult it is for the sound to get through. As window-panes are solid glass, they are therefore, alone, less impactful at reducing the sound than you might expect. Double and triple glazed windows, however, have cavities between the panes of glass filled with either air or denser gas. This creates a natural barrier to the sound, softening the waves considerably before they enter the home.
The thickness of the window-pane will affect which frequencies of sound get blocked out; soundwaves outside this frequency will still pass through. So double glazed windows with two panes the same thickness will still only block out the one frequency of sound. However, by varying the thickness of the panes, you can capture more of the sound’s frequency range, with the first pane capturing one frequency and the next pane capturing another. This dramatically reduces the amount of sound entering your home. It is also possible to get windows specifically designed for certain types of sound, for instance traffic noise, that transmit at a certain frequency.
There are other methods employed to reduce sound, however, these are less effective than varying the thickness of the glass and can impact the cost of the windows significantly. These include:
- A larger gap between panes. This creates greater area for the sound to travel through, however, a gap of 60mm or more is required before the impact is noticeable and this is seldom practical.
- Krypton-filled units. Filling the space between panes with Krypton gas, rather than air or argon also helps to slow the sound travel. However the impact rarely justifies the cost of including the gas.
- Noise Reducing laminate. Adding a laminate coating to glass can have a similar impact to varying the thickness of the glass, without the need for multiple panes.
For further information or to discuss your requirements with our team, fill out our contact form and a member of the Spire Glass team will be in touch to discuss your needs.