Benefits of Secondary Glazing to Soundproof Your Home

double glazing windows

Benefits of Secondary Glazing to Soundproof Your Home

We’ve all been irritated by outside noise before – it’s disturbing and there’s not much you can do but endure.

Picture it: you’ve had a hard week at work and want to have a lie in on the weekend.  All of a sudden at 7am on Saturday the workers renovating next door start shouting to one another and hammering away, waking you up. Another 4 months to go before you get that sleep in.   – sound familiar? You can’t very well ask them to stop their work. While you usually can’t control the noise going on outside you home, you can do something about how much of it comes into your home. With the city growing a little bit busier and noisier each year, there’s never been a better time to consider secondary glazing and soundproofing your windows or doors.

Maximum Air Gap for Best Soundproofing

Secondary glazing systems convert your existing window into double glazing without the hassle of replacement. The secondary window system is retrofitted to the inside of your existing window sill and creates an air gap between the two windows, which is the essence of double glazing.  The large air gap  created by the secondary glazing system is a far more difficult path for sound to travel through. Consequently, fewer sound waves are able to penetrate through the extra layer, leaving the inside quieter and more serene.

Magnetite offers two secondary glazing systems to suit the requirement of your home or office. Magnetite retrofit double glazing is an ideal soundproofing solution for timber or heritage windows due to its slim line frame which blends into the existing window. While Soundtite is also a popular choice for aluminium sliding windows or doors due to its durability, ease of colour matching and it can also be designed to slide vertically or horizontally for ease of use. Both of Magnetite and Soundtite come in a range of glazing thicknesses to meet the level of soundproofing you need for your home or office.

Double glazed windows – More Weight, Less noise

To put it simply, double glazing is an extra layer of glazing in your window which makes the window heavier.  With that extra glazing weight, it is harder for noise to penetrate the window. Sound is created by vibration – the extra mass absorbs this vibration, preventing those sounds from escaping into your house. By installing Soundtite or Magnetite secondary glazing, you’re fundamentally creating a barrier which diminish the volume of outside sounds. Soundproofing your home is an investment in comfort, and one we are yet to see anyone regret.

Why not speak to our Double Glazing Melbourne team today and find how we can soundproofing your windows or doors

Air tight Seal for Maximum Insulation

For a city like Melbourne that has a huge stock of existing homes or buildings, secondary glazing such as Magnetite is a popular option for soundproofing existing windows. The product with which we share our name, Magnetite, is the go-to option for timber or heritage windows. The secondary window panel is snapped onto the subframe with a magnetic seal, creating an air tight barrier of space between the existing window and retrofitted window. This air tight seal is a key element in delivering the high performance of our window system.

In addition to the key advantage of creating a soundproof window, Magnetite retrofit double glazing also improve thermal comfort and increase energy efficiency of your windows. Like Soundtite and the rest of our line, we custom make and install our Magnetite secondary glazing to suit your acoustic or thermal requirements.

Our Magnetite Melbourne customers can’t believe how much of a difference secondary glazing makes for soundproofing and thermal comfort. If you’re looking for soundproofing or double-glazing windows in Melbourne, look no further.

Magnetite is Australia’s leading secondary glazing and soundproofing solution for existing windows, servicing Melbourne, Sydney, Adelaide, Canberra and Perth. Get in touch with our Double Glazing Melbourne experts today to find out how we can help make your home more comfortable.

  1. Conduction
    Heat moving through an object (i.e. heat will travel through an aluminium, or steel frame more easily than through a timber or PVC frame).
  2. Radiant heat
    Heat from the direct sun. It can pass through space until reflected or absorbed.
  3. Convection
    Heat flow resulting from air movement e.g. either 'natural' convection - warm air rises, or 'forced' convection - a breeze by a window, both can result in a draught by a window.
  4. Infiltration
    Air leaks around the frame, around the window sash and through the gaps in the movable window parts.

When evaluating your options to improve the thermal performance of your windows, the following double glazing key performance criteria should be considered:

  • U-Value (Uw) represents heat transfer through a window, irrespective of direct sunlight. The lower a window’s U-Value, the better the insulation performance.
  • Solar Heat Gain Coefficient (SHGC) measures the solar energy that passes through glazing. The lower the SHGC, the less solar heat is transmitted through a window.
  • Air Infiltration or leakage measures the rate at which air passes through gaps in window joins and seals. The lower the air infiltration, the better a window’s energy performance.

The Window Energy Rating Scheme (WERS) Thermal Performance

Aluminium Frame Windows

Glazing Type Cooling Stars Heating Stars Cool% Heat% Uw SHGC
Single glazed 3mm clear glass* half blue star red starhalf red star 7.4 0.77
Single glazed 3mm clear glass &
4.5mm Magnetite
blue starblue starhalf blue star red starred starred starred starred starhalf red star 35% 59% 2.9 0.67

Timber Frame Windows

Glazing Type Cooling Stars Heating Stars Cool% Heat% Uw SHGC
Single glazed 3mm clear glass* blue starhalf blue star red starred starred starhalf red star 20% 28% 5.5 0.69
Single glazed 3mm clear glass &
4.5mm Magnetite
blue starblue starhalf blue star red starred starred starred starred starred star 37% 61% 2.6 0.66
Single glazed 3mm clear glass with
Solartite** and 4.5mm Magnetite
blue starblue starblue starblue starblue starblue starhalf blue star red starred starred starred starhalf red star 76% 45% 1.8 0.20

 

*WERS standard typical industry window
**Solartite is a range of high performance window film. The window tested above has Solartite’s low-e film.


Magnetite vs Traditional Double Glazing – What the experts says

Winter - the ideal situation is to let in as much of the sun's heat and then trap it inside to maintain a comfortable environment in your home or office. This will also significantly reduce heating costs and saves you money. The ideal window for winter will have a high SHGC to let the sun's heat in and a low U-Value to prevent the heat from escaping. Clear windows without shading films are better suited for winter climates.

Compared with traditional double-glazing, Magnetite’s double-glazing solution can provide better results during winter or for cold climate areas such as Canberra, the Adelaide Hills and Blue Mountains.

Magnetite's clear acrylic window panels allow the direct heat from the sun's rays to enter the building and once inside, Magnetite's superior magnetic seals retain the heat, giving Magnetite an advantage over conventional operating windows.

Glazing Type Cooling Stars Heating Stars Cool% Heat% Uw SHGC AI
Double Glazed 3mm clear glass/12mm air
gap/3mm clear glass IGU (Insulated Glass Unit)*
blue starblue starhalf blue star red starred starred starred starred starhalf red star 40% 55% 3.0 0.61 5.0
Single glazed 3mm clear glass &
4.5mm Magnetite
blue starblue starhalf blue star red starred starred starred starred starred star 37% 61% 2.6 0.66 0.5

 

*WERS standard typical industry window

Summer - the ideal situation is to minimize the heat coming in from outside and prevent the cool air inside from escaping through the window. This will make your home more comfortable and reduce your air-conditioning costs. The ideal window for summer, or for a large west-facing window, will have a low SHGC to limit the heat from the sun's direct rays, as well as, a low U-Value to prevent the heat in the air outside from moving through the window and warming the cool conditioned air inside. It is better to have a shading film on the first (outer) glass pane to limit the heat that enters the double glazed unit.

The combination of Magnetite retrofit double glazing and Solartite outperforms the traditional insulated glass unit for hot climate. Magnetite fit over an existing window with reflective film will give better summer heat control than a double-glazed window with supertoned glass.

The Magnetite system stops the conduction and convection of heat better than glass windows giving superior results for summer conditions. Combined with a film or a shading device, Magnetite is the ideal solution for the hot Australian conditions.

Glazing Type Cooling Stars Heating Stars Cool% Heat% Uw SHGC AI
Double Glazed 5mm Supertoned glass/6mm
air gap/5mm clear glass IGU (Insulated Glass Unit)*
blue starblue starblue starhalf blue star red starred starred starred starhalf red star 54% 425% 3.30 0.461 5.0
Single glazed 3mm glass Solartite**
and 4.5mm Magnetite
blue starblue starblue starblue starblue starhalf blue star red starred starred starred star 73% 38% 2.4 0.19 0.5

 

*WERS standard typical industry window
**Solartite is a range of high performance window film. The window tested above has Solartite’s low-e film.

Click here to view pdf version of Magnetite WERS test result.

Noise Reduction Technical Data and Results

Proven Results

Noise pollution is one the biggest problems faced in the cities today, particularly in a high-density living. 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 penetrates windows through leaky seals or vibrations through the window structure. To reduce noise, a window should minimise air infiltration, hold enough weight to limit vibration and allow a large air cavity. This cavity, or air gap, is the key to secondary glazing.

Expert Advice:

CSIRO Research by John Davy shown an air cavity can effectively enhance sound insulation performance. The larger the air cavity the more noise the window system can reduce. Results show a wide air gap of 100-125mm will improve sound insulation by an average of 7dB(A) more than windows with a narrow gap of 8-13mm.

Window or Glass Door Type Total Glass Thickness (mm) Air Cavity Thickness (mm) Sound Insulation (dB)
Single Glaze 3mm 3 0 23
Single Glaze 6mm 6 0 27
Double Glaze Narrow Gap 9-12 8-13 31
Double Glaze Wide Gap 9-12 100-125 38

 

The human ear is less sensitive to low frequency sound. 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.

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. If the glass is laminated there is no perceived difference in noise reduction.

National Acoustic Laboratory Testing:

Working with the principles of noise transfer, Magnetite® and Soundtite are designed for high performance, which is achieved by combining air tight seals with the ability to maximize an air cavity and the flexibility to vary glazing thickness to suit. Magnetite® is excellent at reducing general noise such as busy roads, commuter trains and noisy neighbours. Whereas, Soundtite works well to combat low frequencies noise such as garbage truck, freight trains or airplane during take-off and landing.

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 52%
ATF 1507 Test window, 100mm air gap and Magnetite System (10.0mm acrylic panel) 39 70%
ATF 817 Test window, 100mm air gap and Soundtite (6.38mm laminated glass) 41 78%

 

*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.