Noise Reduction
Technical Data And Results
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.
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 sound levels a window system should have minimal air infiltration and possess enough weight to limit vibration.
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 mm |
3 |
9 |
23 |
|
|
4mm |
4 |
5 |
25 |
|
|
6mm |
6 |
19 |
27 |
|
|
Narrow Gap |
9 to 12 |
8 to 13 |
7 |
31 |
|
Wide Gap |
9 to 12 |
100 to 125 |
10 |
38 |
* taken from: The Australian Window Association's Guide to the Sound Insulation of Generic Types of Windows and Glass Doors By Dr John Davy CSIRO Building, Construction and Engineering April 2000
|
Magnetite is able to utilize these facts to the advantage of the end user. Our magnetic seals
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 |
STC |
Improvement |
|
ATF 707 (test window) |
Aluminium sliding window, 3mm float glass with mohair seals |
23 |
NA |
|
ATF 748 |
Test window, 100mm air gap and Magnetite System (4.5mm acrylic panel) |
36 |
13 |
|
ATF 747 |
Test Window, 100mm air gap and Magnetite System (6.0mm acrylic panel) |
37 |
14 |
| ATF 1505 (test window) |
Aluminium sliding window, 3mm float glass with
|
23 | NA |
| ATF 1506 | Test window, 100mm air gap and Magnetite System
(8.0mm acrylic panel) |
38 | 15 |
| ATF 1507 | Test window, 100mm air gap and Magnetite System
(10.0mm acrylic panel) |
39 | 16 |
| ATF 1508 | Aluminium sliding window, 6.38 laminated glass 100mm air
gap and Magnetite System (8.0mm acrylic panels) |
39 | 16 |
*STC is the Sound Transmission Class of the window and is measured over a range of frequencies. The STC represents the corrected, average reduction in decibels (dB) measured at 500Hz.
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%
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