Noise Reduction Technical Data and Results
Noise has wave properties. This means that noise can pass through a window in two ways:
1. Crack space or poor seals are responsible for letting noisy air enter through small spaces, allowing noise to amplify once inside.
2. Vibration allows noise to travel through solid objects increasing noise levels inside.
This means that to effectively reduce noise sound levels a window system should have minimal air infiltration and possess enough weight to limit vibration. Magnetite double glazed window systems meet these criteria.
Expert Advice:
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.
| Window or Glass Door Type | Total Glass Thickness (mm) | Air Cavity Thickness (mm) | Number of Measurements Averaged | Sound Insulation (dB) |
|---|---|---|---|---|
| 3 | 3 | 3 | 9 | 23 |
| 4 | 4 | 6 | 5 | 25 |
| 6 | 6 | 34 | 19 | 27 |
| Narrow Gap | 9-12 | 8-13 | 7 | 31 |
| Wide Gap | 9-12 | 100-125 | 10 | 38 |
Magnetite is able to utilize these facts to the advantage of the end user. Our magnetic seals provide one of the lowest air infiltration rates of any operational window.
Our slim extruded framing allows us to maximize the air cavity obtained for all window types.
This allows us to use acrylic glazing, which is safer and lighter than glass in our window system.
Whereas traditional double-glazing uses thick glass and a narrow air cavity, Magnetite is able to use safer, more manageable acrylic with a larger air cavity.
Magnetite is excellent at reducing noise in the frequencies from 400Hz to 20,000Hz. This is ideal for reducing noise from busy roads, commuter trains, and noisy neighbours.
National Acoustic Laboratory Testing:
| Test Code | Material Tested | Rw* | Improvement |
|---|---|---|---|
| ATF 707 (test window) | Aluminium sliding window, 3mm float glass with mohair seals | 23 | N/A |
| ATF 709 | Test window, 100mm air gap and Magnetite System (4.5mm acrylic panel) | 35 | 12 |
| ATF 1507 | Test window, 100mm air gap and Magnetite System (10.0mm acrylic panel) | 39 | 16 |
*The Weighted Sound Reduction Index (Rw) is a measure for sound insulation performance of a single building element such as windows. The higher the Rw rating, the better the sound insulation.
According to a study released by the CSIRO the human ear needs a change of 3dB to detect a difference in noise levels and the human ear perceives a change of 10dB as a doubling or halving of the noise level.
1. If you double the thickness of glass in a window the noise level will decrease by 3dB – the least amount possible to make a difference.
2. If the glass is laminated there is no perceived difference in noise reduction.
Testing has shown that the addition of Magnetite panels can reduce the noise level through your window by up to 70%.
