Acoustic Properties of Double Glazed Units
Noise pollution is one of the biggest problems faced in cities today. Unwanted noise can be responsible for sleep loss and lack of concentration. This can lead to a deterioration of health through increased stress levels, headaches, high blood pressure and loss of hearing.
Research by Dr. John Davy at the CSIRO has shown that secondary windows will reduce more noise than single glazed windows or even traditional double glazed units. This is due to the large buffering air cavity between two windows. The larger the air cavity the more noise the window system can reduce. Noise has wave properties. This means that noise can pass through a window in two ways:
- Crack space or poor seals are responsible for letting noisy air enter through small spaces, allowing noise to amplify once inside.
- Vibration allows noise to travel through solid objects increasing noise levels inside.
This means that to effectively reduce sound levels a window system should have minimal air infiltration and possess enough weight to limit vibration.