MAIN >> NOISE BARRIERS >> ALTERNATIVES TO BARRIERS

Apart from noise barriers there are other methods of mitigation including quiet road surfaces, the insulation of properties and even tunnelling. In many cases using a combination of different methods can lead to a better all round result. For example, in the Netherlands the use of porous asphalt has reduced road traffic noise enormously when traffic is travelling at high speeds, allowing planners to keep barrier heights to a minimum. Constructing barriers out of sound absorptive materials also assists this.

Building roads in tunnels is one alternative that does not require noise barriers. However this is a costly option and, unless there are other factors that require a tunnel be built, it is unlikely it would justify the expense. The building of roads on viaducts can also be used to reduce traffic noise. However this is nearly as costly as tunnels to build (although maintenance costs are much lower) and does not have any aesthetic advantage over noise barriers at all, in fact is probably visually worse as it allows roads to take over the landscape.

The Main Roads Department, Western Australia report on Night-time Noise Levels claims that "Noise mitigation measures have largely been confined in Australia to the installation of acoustic barriers (with the notable exception of New South Wales), where the Shire of Hornsby has enacted a code of practise for the noise insulation of new houses. The continued installation of high noise barriers as a single attenuant against the intrusiveness of road traffic noise cannot continue from both an economic and aesthetic perspective. Serious consideration should be given to the initiation of a research and development program including a national code for the appropriate installation of noise mitigation measures."

A publication of Vic Roads and the Victorian government called A Guide to the Reduction of Traffic Noise lists many ways traffic noise can be reduced without the use of noise barriers. These include:

• Keeping as much space between roads and noise sensitive areas (such as bedrooms) as possible. This can be achieved by building on the other end of the block, and building bedrooms at the rear of the house.
• Excavating to provide a shield from traffic noise.
• Avoiding having windows facing onto the road.
• The use of dense insulation in walls and double glazing of windows.
• Making sure cracks around windows and doors are well sealed.