Traditional timber sash windows were made to operate using cords and weights. They were used in many period homes, including Georgian, Victorian, and Edwardian properties.
However, today it is also possible to have sash windows that don’t operate using cords and weights. This alternative, more modern, style of sash window is called a spiral balance sash window and was patented in 1930 (source).
What is a spiral balance sash window and what benefits does it offer?
Spiral balance sash windows, sometimes also referred to as spring sash windows, operate using a spiral rod within a tube that is connected to a spring. The tension from the rod and spring ensures that the window does not drop when it is opened and operates smoothly.
Although spiral balance sash windows are a more modern version of the sliding sash windows, they can still be made in timber and can still use traditional details, such as sash horns. This means that spiral balance sash windows can suit both period properties and more modern buildings.
However, unlike cord hung sash windows, spiral balance sash windows do not require as much space in the box frame of the window. This is due to them not needing space for the weights to move freely and means that they can be fitted in locations that were not originally designed to hold a cord hung sash window, where there may be a smaller reveal.
What is a cord hung sash window and what benefits does it offer?
Cord hung sash windows work by having counterweights hidden within the box frame of the window that are connected to the sashes (the moving part of the window) using cords. When you open the window, these weights offset the weight of the sashes to enable the window to stay open.
In properties where there is space for a box window frame, there are several benefits to having cord hung sash windows.
The traditional appearance suits period properties with traditional sash window openings and means that you have a cord on show at the side of your windows rather than a plastic tube.
Cord hung sash windows are also a simpler mechanism. This means that cords and weights can be replaced relatively easily if damaged, whereas spirals are more complicated to replace if they snap.
If you are worried about energy efficiency, cord hung sash windows can still be made to be double glazed and draught proofed, providing all the thermal benefits of modern windows.
Are you looking to replace or upgrade your sliding sash windows?
At The Sash Window Workshop, we are timber window specialists and have extensive experience manufacturing and installing both cord hung and spiral balance sash windows.
For a free, no obligation quotation, contact us on 01344 868 668.