A short history of wooden windows

Wooden sash windows have been around for a long time. They were designed and in use by the Europeans at home long before Australia was settled by them. And while certain elements of windows have changed, the basic design and mechanics have been the same since the start.

In the seventeenth century pulleys and weights were first applied to timber sashes and frames and the double sash window was born. They were installed throughout the United Kingdom in the 1680s and 90s.

These very early windows had very chunky and solid frames (stiles and rails). The sashes were divided by small wooden rails or
mullions which suited the limited size of the poor quality glass. The wood used was generally heart wood, which is much better quality and long lasting than newer woods used in building.




The eighteenth century brought larger panes of glass and slimmer timber profiles. By the middle of the century the familiar Georgian window with 6 panes to each sash had become common. These windows were glazed with a better quality of glass. Often known as crown glass it had curved ripples, air bubbles and distortion which can still be visible. Glass like this is no longer made so it is important to keep it in historic buildings when possible. Sometimes however it has to be replaced because it is damaged during repairs or too dangerous to leave because of cracks. Some glass is so thin that it does not stop heat transfer or noise very well.

The Georgian pattern continued to be popular in the nineteenth century but other configurations such as lying or horizontal panes were also being developed. Larger, heavier panes of glass became more common and eventually sashes were glazed with single large panes of plate glass.

Sash frames and joints were strengthened to suit, for example horns were invented so that joins did not rely on the wooden dowel, or tenon, to hold the weight of the window. Horns are another part of the window that often have to be replaced.

Replacement 'horn' for top sash window.

Replacement ‘horn’ for top sash window.

The 'horn' from the top sash before repairs.

The ‘horn’ from the top sash before repairs.


As large panes became fashionable, old sashes with multiple small panes were sometimes altered – their glazing bards were removed and they were glazed with larger panes of plate glass.

At the end of the nineteenth century and start of the twentieth century small paned sash windows, sometimes with chunky glazing bars, became briefly popular again, mostly as a reaction to the trend towards ever-larger panes.

Windows of this period can often combine a multiple small paned upper sash with a single or two pane lower sash. Upper sashes from this period sometimes incorporate stained glass, a feature that was to remain into the 1930s.

In the mid 1950s the wooden sash as we know it started to fall out of fashion, leaving, however over 200 years worth of wooden sash windows in buildings throughout Australia. Old sash windows are both significant and important to architecture and our built heritage. If cared for they can last for many, many years. So if your beautiful sash windows are looking a bit worse for wear get in touch with the team at Sealasash today.

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 Colm  0404 641 206  John  0400 478 666

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 Colm  0404 641 206  John  0400 478 666

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 Henry  0468 675 833

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 Colm  0404 641 206  John  0400 478 666

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