Installing a good quality double glazing system will give a substantial reduction in the decibel level of noise permeating through windows from typical town traffic or a local playground. However, if your noise problem is more acute, noise prevention is a more extensive technical matter – the actual source of the noise, the location of the house, the type of glass thickness needed, the distance the two panes are set apart and any additional insulation around windows or between the double glazing should all be considered. Professional advice should be sought from a quality double glazing company or building company on other methods of sound insulation.
Government grants to install double glazing can be given to people living in certain heavy traffic areas or where there is an airport nearby. Your local authority will be able to supply details and advice. In normal noise level situations the two sheets of glass in a double glazing system should be at least l00mm apart to provide adequate sound insulation. To provide effective thermal insulation, the optimum gap should be of 20mm. If you want both sound and thermal insulation, you should select a wider gap or use triple glazing ; you will find thermal insulation is not greatly reduced in this case.