Slimline double glazing

The technology of Double Glazing is no different to other aspects of technology in that over time new developments are introduced which seek to improve the standards that currently exist.

Slimline double glazing is a modern innovation which has taken the concept of Double Glazing to a new level.

Conventional double glazing consists of two layer of sealed glass which can have a gap between which may be as much as 25 millimetres wide. The cavity will be filled with dry air or an inert gas. The reduced thermal conductivity of the gas and the extra layer of glass will provide greater insulation than a single pane.

In slimline double glazing the sealed cavity between the two panes is greatly reduced resulting in a sealed unit that is significantly thinner than a conventional double glazed unit. All air is removed and a vacuum created. In production, air is sucked out of the glazing unit through a small tube in the corner of one pane of glass. This is melted and closed at the end of the process.

A typical thickness of a slimline glazed unit is in the order of 8.5 millimetres but can be less. In a standard double-glazed unit, a gap this small without the creation of a vacuum would continue to conduct heat but here it is said the glazing works in the same way as a vacuum flask – the vacuum eliminates the heat flow between the two glass plates

What are the benefits of Slimline Double Glazing

With this reduced thickness of unit the Slimline units greatest advantage is that it is possible to use it in existing windows where they were designed to be used with single panes and are unable to hold the thicker double glazed unit. Fitting it into new windows reduces the level of heat loss beyond that achieved by double glazing.

To builders, architects and designers the introduction of this unit has come as a breath of fresh air. It enables the introduction of increased insulation and comfort factors associated with double glazing into situations that would present a problem using more conventional double glazing products.

As slimline double glazing can be carried out on existing wooden framed windows it is more likely yo overcome the previous objections from Planning authorities in buildings that are listed or are in conservation areas. Window manufacturers can choose to use wood in new window construction using smaller timber sections. Fitted into existing windows it is possible to apply putty to fix the units in place.

One criticism of the double glazed unit is that to some the glass is said to be noticeable. This is due solely to the thickness of the unit. With slimline double glazing the glass is not visible and as such is considered more acceptable in listed buildings where outward appearance is often crucial.

The high performance slimline double glazed units produce a centre pane U value as low as 1.4, compared to a single glazed window u-value of 5.4. The heat insulation value is expressed as a 'U' value, the lower the u-value the better the insulation level.This lower level u-value easily conforms to the Building Regulation requirements thereby satisfying all local building control, planners and conservation officers.

Cost Comparisons

It is inevitable with two similar systems,Conventional Double Glazing and Slimline Double Glazing that cost comparisons are considered. It is impossible to be specific when referring to the possible cost of Double glazing as every window and window opening has to be considered. We can however consider some generalisations.

When considering the relative cost of Double Glazing panels as opposed to Slimline panels it has to be said that the method of construction makes the Slimline glazing unit marginally more expensive per unit. However this can be offset by the fact that the slimline unit used in new installations uses slimmer sectioned framing material thereby reducing that cost and balancing out the increased cost of the glass unit.

As the major benefit of slimline units is their use in a traditional existing window., cost comparison becomes something of an irrelevance as no other form of double glazing can be fitted into an existing opening.

In short slimline double glazing has a greater flexibility of use than double glazing and in certain circumstances may reduce costs by avoiding the necessity to replace a window whilst achieving the benefits of double glazing.