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Double Glazed Units


What are double glazed units?

Double glazing means that there are two glass panes in the window, rather than one. Typically, double glazed units comprise a 4mm pane of glass, a 12mm or 16mm gap and then another 4mm pane. These units are all assembled and then inserted into the window by hand. The presence of Argon gas within the unit slows the movement of warm air within the glass unit. Other gasses can be sourced, Krypton for example, if you need more heat insulation.

The low-emissivity coating means that these double glazed units are designed for optimal energy efficiency. They also help to retain thermal energy by reflecting heat back to its source.

By and large, double glazing is enough for the weather in the UK. Although we can provide triple glazing, in most cases we would recommend our customers to go with the standard option of double glazing as it’s all they typically need.

What is low emissivity glass?

Our low emissivity glass ensures that you stay comfortable whatever the season by reflecting expensive radiator heat back inside during the winter months and reflecting heat from the sun back outside during the summer. It also helps to significantly reduce both your carbon emissions and your energy bills. Our double glazed units are additionally available in toughened, laminated, satin and acoustic (sound reducing) options.

What is the benefit of double glazing?

Double glazing is actually good for the environment in many ways, in addition to keeping you warm. The energy saving reduces the amount of wasted power, and the timber can be recycled from the frames (unlike plastic windows). With single glazing much of the energy you use to heat your home is wasted. With double glazing, your home is far more energy efficient. So as well as helping the environment, you’re helping yourself by staying warmer during the cold months!

For Sash Only Replacement*:

Unit Thickness:   20mm.
Pane 1:               ExtraClear Float, 4mm.
Spacer:              White ‘Warm Edge Super Spacer’, 12mm.
Gas Fill:              Argon (90%), Air (10%).
Pane 2:              ClimaGuard Premium2 ExtraClear Float, 4mm.
uValue:               1.3 W/m2k.

For Full Box, Casement and Door Replacement*:

Unit Thickness:   24mm.
Pane 1:               ExtraClear Float, 4mm.
Spacer:              White ‘Warm Edge Super Spacer’, 16mm.
Gas Fill:              Argon (90%), Air (10%).
Pane 2:              ClimaGuard Premium2 ExtraClear Float, 4mm.
uValue:               1.1 W/m2k.

*All Technical Specifications are calculated in accordance with EN410. Illustrated specifications are standard, but alterations are available upon request.

Building Regulations require Safety Glass to be provided, by law, in areas where human impact is seen as a reasonable hazard. This includes windows where the glass panes are at a height of 800mm of the floor or lower, glazed areas of a door within 1500mm of the floor, or in a product within 300mm of a door. Many customers, however, also choose to upgrade to Safety Glass even where there is no legal requirement, purely for the peace-of-mind and security that the increased strength brings.

The same high quality float glass used in our standard Double Glazed Units undergoes an additional tempering process, resulting in a glass that is significantly tougher than its un-tempered counterpart.

The increased compressive stresses imparted by the tempering process means that if a Toughened Glass pane is broken, the glass breaks into small, harmless cubes instead of larger, jagged shards.

For Sash Only Replacement*:

Unit Thickness:   20mm.
Pane 1:               ExtraClear Float, 4mm.
Spacer:              White ‘Warm Edge Super Spacer’, 12mm.
Gas Fill:              Argon (90%), Air (10%).
Pane 2:              ClimaGuard Premium2 ExtraClear Float, 4mm.
uValue:               1.3 W/m2k.

For Full Box, Casement and Door Replacement*:

Unit Thickness:   24mm.
Pane 1:               ExtraClear Float, 4mm.
Spacer:              White ‘Warm Edge Super Spacer’, 16mm.
Gas Fill:              Argon (90%), Air (10%).
Pane 2:              ClimaGuard Premium2 ExtraClear Float, 4mm.
uValue:               1.1 W/m2k.

*All Technical Specifications are calculated in accordance with EN410. Illustrated specifications are standard, but alterations are available upon request.

Building Regulations require Safety Glass to be provided, by law, in areas where human impact is seen as a reasonable hazard. This includes windows where the glass panes are at a height of 800mm of the floor or lower, glazed areas of a door within 1500mm of the floor, or in a product within 300mm of a door. Many customers, however, also choose to upgrade to Safety Glass even where there is no legal requirement, purely for the peace-of-mind and security that the increased strength brings.

Two 3mm panes of float glass are sandwiched together using a thin sheet of PVB (polyvinyl butyral), resulting in a ‘composite pane’ roughly 6.5mm thick. One of these ‘composite panes’ is then used to replace one or both of the two 4mm panes in a standard Double Glazed Unit.

This PVB layer ensures that the glass panes stay ‘glued’ together, even if exposed to extreme force, which not only makes Laminated Glass a great alternative to Toughened Glass, but also means that it is incredibly difficult for a burglar to ‘break through’ a Laminated Double Glazed Unit. The increased pane thickness also provides an extra level of sound insulation, in addition to the already increased sound reduction that comes naturally from Double Glazing, making it perfect for helping to block out the constant drone of London traffic.

For Sash Only Replacement*:

Unit Thickness:   20.76mm.
Pane 1:               ExtraClear Float, 3mm / PVB, 0.38mm / ExtraClear Float, 3mm.
Spacer:              White ‘Warm Edge Super Spacer’, 8mm.
Gas Fill:              Argon (90%), Air (10%).
Pane 2:              ExtraClear Float, 3mm / PVB, 0.38mm / ClimaGuard ExtraClear Float, 3mm.
uValue:               1.7 W/m2k.

For Full Box, Casement and Door Replacement*:

Unit Thickness:   24.76mm.
Pane 1:               ExtraClear Float, 3mm / PVB, 0.38mm / ExtraClear Float, 3mm.
Spacer:              White ‘Warm Edge Super Spacer’, 12mm.
Gas Fill:              Argon (90%), Air (10%).
Pane 2:              ExtraClear Float, 3mm / PVB, 0.38mm /  ClimaGuard ExtraClear Float, 3mm.
uValue:               1.3 W/m2k.

*All Technical Specifications are calculated in accordance with EN410. Illustrated specifications are standard, but alterations are available upon request.

Two panes of high quality float glass (the same used in our standard Double Glazed Units) are sandwiched together with thick sheet of PVB (polyvinyl butyral) to form an 8.5 mm ‘composite pane’. This composite pane then replaces one of the 4mm panes in our Standard Double Glazed Units.

An Acoustic Double Glazed Unit provides increased sound reduction, compared to a Standard Double Glazed Unit, due to an additional 4mm pane of glass and increased sound reduction, compared to a Laminated Double Glazed Unit, due to an additional 0.12mm of PVB (polyvinyl butyral) membrane.

Furthermore, different thicknesses of glass are more effective at reducing certain frequencies of sound. This is due to sound having different wavelengths, and thus, different distances that the wave must travel in order to complete a full ‘wave’. So, by including different panes of different thicknesses (1x 8.5mm composite pane & 1x 4mm pane) within the DGU, you are increasing the range of frequencies at which the unit can effectively reduce sound.

For Sash Only Replacement*:

Unit Thickness:   20.50mm.
Pane 1:               ExtraClear Float, 4mm / PVB SR, 0.50mm / ExtraClear Float, 4mm.
Spacer:              White ‘Warm Edge Super Spacer’, 8mm.
Gas Fill:              Argon (90%), Air (10%).
Pane 2:              ClimaGuard Premium2 ExtraClear Float, 4mm.
uValue:               1.7 W/m2k.

For Full Box, Casement and Door Replacement*:

Unit Thickness:   24.50mm.
Pane 1:               ExtraClear Float, 4mm / PVB SR, 0.50mm / ExtraClear Float, 4mm.
Spacer:              White ‘Warm Edge Super Spacer’, 12mm.
Gas Fill:              Argon (90%), Air (10%).
Pane 2:              ClimaGuard Premium2 ExtraClear Float, 4mm
uValue:               1.3 W/m2k

*All Technical Specifications are calculated in accordance with EN410. Illustrated specifications are standard, but alterations are available upon request.

A Satin Double Glazed Unit can be made from any Standard, Toughened, Laminated or Acoustic Unit mentioned above, and serves to obscure the view of whomever tries looking through the Unit whilst having no negative impact on the level of natural light that is allowed to enter.

The Satin effect is produced by sandblasting or chemically etching one side of one of the glass panes in the unit, which is then fitted internally facing to ensure a smooth exterior finish. This type of glass is perfect for any room where privacy is a priority, such as a bathroom or WC, and can be added to individual sashes within a window for increased flexibility.

Click here to view or download a catalogue of obscured glass options.

For Sash Only Replacement*:

Unit Thickness:   20mm.
Pane 1:               ExtraClear Float, 4mm.
Spacer:              White ‘Warm Edge Super Spacer’, 12mm.
Gas Fill:              Argon (90%), Air (10%).
Pane 2:              ClimaGuard Premium2 ExtraClear Float, 4mm.
uValue:               1.3 W/m2k.

For Full Box, Casement and Door Replacement*:

Unit Thickness:   24mm.
Pane 1:               ExtraClear Float, 4mm.
Spacer:              White ‘Warm Edge Super Spacer’, 16mm.
Gas Fill:              Argon (90%), Air (10%).
Pane 2:              ClimaGuard Premium2 ExtraClear Float, 4mm.
uValue:               1.1 W/m2k.

*All Technical Specifications are calculated in accordance with EN410. Illustrated specifications are standard, but alterations are available upon request.

Argon and Krypton are odourless, colourless, non-toxic inert gases that are used instead of air between panes of glass to increase insulation and energy efficiency. Argon is the cheaper, more readily available gas, but Krypton is a better insulator. Our windows use Argon as standard because it works well in the UK climate, so for most customers there is no need to upgrade to Krypton. However, if we need to supply windows in our heritage range, we’ll use Krypton because of the limited space in those units.

Modern Heat Retention and Sound Reduction Technology!

call us: 020 3302 2060 or email: [email protected]

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