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Tel: 0208 893 4420
Fax: 0208 867 2767


Tel: 0800 043 1054
Fax: 0208 867 2767

“If we are truly concerned with conserving our architectural heritage then faithful reproduction of the windows and doors, using traditional construction methods and individual glazed panels to create a varied light reflection across the whole window is a critical factor to be considered. Stick-on glazing bars should not be an acceptable option for period windows inside conservation areas or in listed buildings”

S. T. F. Craig RIBA

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Why Slimline Units?

Slimline double-glazed units have narrower cavities between the panes of glass than standard double-glazing units, and look just like single glazing, making them ideal for windows on listed, conservation and period properties.

With slimline double-glazing, from the exterior and the interior (unless you look very closely), you can’t tell that the windows have double-glazing fitted – which is vital to retain the original character and value of a period property.

The thermal efficiency of slimline double-glazing can also now be even better than standard double-glazing, achieving U-values (the term used to measure thermal efficiency) of as low as 1.2 Wm2K on a 6mm gas-filled cavity, depending on the type of gas fill used.

The reduction of heat loss through slimline units is up to 77 percent as when compared against single glazing, and it is possible to achieve Part L building regulations for thermal efficiency with windows fitted with slimline double-glazing.

Our slim double glazing is also available in a wide variety of glass types, including reproduction Crown glass, which has the authentic uneven reflection of the original glass. This means that period property owners can benefit from all the insulation benefits of double glazing, whilst replicating the original design of their period windows, including the narrow glazing bars which are crucial to maintaining a truly authentic appearance.

Timbalite slimline double glazed units are characterised by their exceptionally low failure rate as well as their thermal efficiency and authentic look, and have been approved by planning authorities for listed and conservation properties throughout the country.

For more information have a look at our Top 10 reasons for choosing slimline double-glazing over standard double-glazing for conservation, listed and period properties.