How do I block road noise?
Blocking road noise is one of the most common residential noise reduction requests today. The three key elements to effectively block traffic noise are:
- Noise barriers within 10 metres of the road
- Quality acoustic fences or noise walls
- White or pink noise to mask traffic sounds
Proximity to the road
To successfully block the road noise, the noise barrier needs to be as close as possible to the road; the wall or fence has to physically reflect or ‘bounce’ the noise away before it gets to the house. Furthermore, sound travels differently the farther it travels. For the first 10 metres, sound travels in straight lines; after that, it changes to vertical waves, getting bigger as they travel.
What does this mean for blocking road noise? It means that it’s best if your noise barrier is located within that first 10m. If it’s 20-30m away, your noise wall or acoustic fence will have to go higher to reduce the noise. After 30m, that traffic noise starts to disperse into the air around you, making it incredibly difficult to block it anymore.
Acoustic fencing and noise walls
An acoustically rated fence or wall can efficiently reflect road noise, especially when designed and installed specifically for your needs. As mentioned above, the wall or fence will work best if built within the first 10 metres of the road. But there are other factors that must be met also:
- Density. A noise barrier requires a certain density to perform acoustically. For instance, brick, block and modular walls all offer strong noise reduction benefits. However, steel and timber do not usually have the density to reduce noise.
- No gaps. Noise, like water, can trickle through any gaps. For best acoustic performance, ensure your acoustic fence or wall sits flush with the ground and is solid all the way to the top.
- Height. As a general guide, line of sight is a good judge of whether the sound can still reach you. If your wall is too low, noise can easily spill over the top. If you’re on the high side of the street, you’ll need a higher wall to block the noise of traffic.
Drown out road noise with white noise
If it’s a steady hum of tyres you still hear, white or pink noise could be the final step to a perfectly peaceful home. You may have heard this as a noise control measure for office spaces, or for the nursery of a very sound-sensitive newborn; here’s how it could help you block traffic sounds.
White noise is made up of a combination of all different types of frequencies; similar to the sound of static. Since human ears can only process a set number of frequencies at once, it uses a greater level of ‘hearing power’ to hear the white noise; this can help mask other noises we find irritating.
Pink noise follows the same principles. However, it focuses on lower frequencies, making it more similar to the sounds of nature — the crash of waves, the trickle of a stream, a rushing breeze. These natural sounds are also found to reduce stress and boost overall happiness, whilst also seamlessly fitting into any outdoor setting.
Items such as wind chimes, water features, or even DIY white noise machines can help you tackle that last, lingering thrum of traffic and block road noise for good.
Written by Evelyn Kandris