You gently lift and a window slides silently and effortlessly open. It’s a wonderful feeling, but there’s a lot of science behind developing the perfect sash window. At Ventrolla, sash windows are hand-made by our team to exact specifications. You can immediately see the craftsmanship that goes into a Ventrolla sash window: the beautiful period detail and the millimetre precision joinery. But what about the science and craftsmanship that you can’t see? How does the interior mechanism of a sash window work? Let’s take a look behind the magician’s curtain…

What are sash cords?

Sash cords are the slender ropes that you see inside the casement of a sash window. These cords are the secret to balancing the weight of the window, so that the bottom panel will slide up effortlessly.

How does a sash cord work?

Much of the functionality is hidden inside the casement of the window. The cord is looped over a service pulley, and is attached to a metal counterweight. Through this counterweight and the multiplied force of the pulley, the weight of the window panel is minimised.

What’s so special about a Ventrolla sash cord?

Ventrolla sash windows are hand-made by experts to millimetre precision. The sash cords correct sash balance to ensure a perfect slide to your window. All of the elements of the sash cord: the cord, the pulley and the counterweight are high quality components built to last.

If you’d like more information about the construction of Ventrolla sash windows, please contact our team.