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Tel: 0800 043 1054
Fax: 0208 867 2767

Thermally Efficient Slimline Double Glazing

Thermally efficient slimline double glazing

Thermally Efficient Double Glazing that looks like Single Glazing

Modern double glazed units are usually not suitable for listed, conservation and period properties, as they are bulky and ruin the character and value of the property, but single glazed windows lose a lot of heat.

Slimline double glazing is ideal for replicating the appearance of single glazing in traditional timber windows, as it has a narrower cavity between the panes of glass than standard double glazing, and can even include an outer pane of restoration ‘crown’ glass to maintain the authentic look of period properties.

The challenge is to ensure these slimmer double glazed units are as energy efficient as thicker standard double glazing, to provide all the benefit and comfort of double glazing without compromising the character or value of the property.

Timbalite slimline double glazed units have a number of features which mean they achieve thermal efficiency that can be even better than standard double glazing – achieving possible U values of just 1.5 W/m2K on a 4mm cavity, and 1.2 W/m2K on a 6mm cavity, depending on the type of gas fill used. The reduction of heat loss through the glass is up to 77 percent as when compared against single glazing.

This is achieved through a number of ways:

1. Gas type

In double glazing, the gap between the two panes of glass is filled with gases which are poor conductors of heat, to improve thermal efficiency and reduce heat loss. At Timbalite we use particularly dense, inert gases such as Krypton and Xenon, to maximise thermal efficiency.

2. Glass type

Different types of glass offer different levels of thermal efficiency. Modern double glazing units include a ‘Low E’ (low emissivity) coating, which reflects heat back into the building and offers far better thermal insulation than plain uncoated glass.

As standard, at Timbalite our slimline glazing units include Softcoat 1.1 glass as its Low E pane, which is more thermally efficient than traditional hardcoated glass, such as K glass, and it also does not carry the same amount of colour.

3. Warm edge spacer bars

The perimeter spacer bar sits between the two panes of glass in double glazing to hold them apart, and contains desiccant to absorb any moisture which may be in the unit. On standard double glazing this spacer bar is often made of aluminium – which is highly conductive and is the cause of heat loss around the perimeter of the pane.

At Timbalite we use warm edge spacer bars called the Super Spacer, which is made of a pre-desiccated, structural foam, and can increase the internal edge temperature of the glass by up to 65% compared to aluminium spacers.

For more information or advice on the choices of slimline double glazed units available, get in touch to speak to one of our experts.

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