Sash history

A legacy from the 17th century, the vertical sliding sash window is enjoying a resurgence of popularity in the UK and, today, is recognized as an outstanding symbol of simple and functional style.

The majority of traditional sash windows are box frames in which pulleys are set and weights hung to counterbalance the sashes. A variation to the traditional weighted sash is the horizontally-sliding ‘Yorkshire’ sash which, despite the name, appears in many English counties, including Sussex, our main supply area.

In the 17th century, with glass being expensive to manufacture and only available in small sizes, an arrangement of six panes in each sash was fairly common. Over time, glazing bars became thinner and more refined and windowpane numbers often increased. This trend reached its zenith in the Regency period with beautiful and graceful window designs adorning fine townhouses across the land. The development of plate glass also affected architectural style in the mid 19th century, and many older multi-paned windows were substituted by four-paned windows while from shortly after this period, houses sported large single pane sashes of the type widely seen today.

The craftsmanship involved in the production of early windows is significant and their individuality is equally noticeable. This can be seen in various ways, for example, in the numbering of sashes to sash boxes and in the subtle “flaws” contained within the original glass. Sash windows were not only the products of skilled workmanship, they also used the highest standard of timber and materials, the living proof of this being their longevity - they have literally withstood centuries of wear.

In contrast, many modern materials used in window construction begin to yellow and crack after 10 to 15 years. Even timber windows, made to original designs, do not necessarily have the durability of their older counterparts. By comparison, a window built in the 18th, or 19th century can be salvaged virtually intact, forming a superior quality foundation for the future. This means that even windows considered ‘beyond repair’ may have only superficial deterioration and can continue to provide, quite literally, further centuries of wear. For these reasons we recommend retaining original fittings wherever possible. Furthermore, a simple, but thorough overhaul, can often address issues such as rotting sash cords, whilst re-balancing weights can ensure that sashes will slide smoothly and for these reasons we recommend regular maintenance schedules.

The sash assembly comprises a sash box, or overall frame, that houses the articulated parts of the window. Inside of the box are the two sashes themselves. These are called the upper and lower sashes. Each sash has its own sash cord and counter-balanced weight running within the hollow frame of the sash box. Using these each sash light can slide independently within the frame yet remain in an open position without props, pegs or wedges. The articulation of a sash window is shown in the animation to the right.

Extracted from Townhouse Times, the official publication of The Regency Town House