Whether you refer to them as sash windows, box sash windows or sliding sash windows, there is only one way to operate them. Sash windows are comprised of a window with one or two sashes which can be opened vertically by pushing and sliding the lower sash upwards.

Sash windows work on a pulley system, making it possible to push your window upwards and pull it back downwards. It is this pulley system which makes sash windows stand out from standard windows and adds to their traditional charm.

A ‘double hung’ sash window means that you can slide both the bottom sash upwards, or slide the top sash downwards, so the window is open at both the top and bottom.

Double hung sash window

Double hung sash window

Components of a sash window that you need to know and understand

Before we take a closer look at how sash windows operate, take a moment to recap the components of a sash window. This will help you to understand our explanation on how they work.

How do traditional sash windows work?

A traditional sash window is often referred to as ‘double hung’ because it features two moveable sets of sashes within the box frame. This means that the window can be opened by sliding the bottom panel up, as well as by sliding the top panel down. By contrast, single hung sash windows only allow ventilation through a single operable lower sash.

The two sashes slide up and down, using a pulley and weight mechanism inside the window frame. When a sash is opened, the weight counterbalances with a weight inside the window frame. The weight connects to the opened sash through a cord that runs over a pulley at the top of the window frame. This method is a cord, weight, and pulley mechanism.

Typically, sash windows are designed in such a way that the pulley mechanism is hidden within the sash frames so, they do not distract from the beauty of the window itself.

Traditional sash windows have many benefits, including an extra safety precaution for homeowners with young children in the house.

Components of a sash window

How has the operation of sash windows changed over time?

In recent years, spiral balance sash windows have become increasingly popular which are simply a modern version of the traditional weight and pulley range. Simply put, the traditional lead and steel weights are replaced by a cords and spring balances (a spring-loaded device) to counterbalance the sash windows. Spiral balances are thought to be slightly more flexible than the traditional weights, making it easier to open the windows. Spiral balances hold the weight of each sash and maintain their position while the windows remain open.

Nowadays, there are also a number of security measures that can be added to sash windows to make them safer for homes with young children and pets including, safety restrictors, safety guards and sash locks.

How do modern sash windows operate?

As with traditional sash windows, modern sashes have their working mechanisms hidden in the frames. However, some modern systems use cords and a loaded spring mechanism (spiral balance) instead of a traditional weight and cord system. When the sashes are moved upwards or downwards, the spring loosens or tightens while the window remains open due to the spring’s tension that releases a countering force.

If you are looking for a professional joiner for Sash window repair or replacement in your property, our team here at Parsons Joinery, would be happy to chat through your requirements and provide you with an obligation free quote.