Single and double-hung windows rose to popularity in the 17th century, and they were kept open with either a pin-and-hole system or by using a stick or other object to prop the sash open. As this style of window became more and more common, new and better ways of keeping them open were created.

One of the earliest mechanisms used for raising and lowering sash windows was a window rope and weight balance — often referred to as a cord and weight system. To support the window in its open position, a cord was attached to the sash frame and then run through a pulley system that was attached to the window frame. The cord was then attached to weights that counterbalanced the weight of the sash. This counterbalance allowed the window to slide effortlessly in the frame and stay put in any position.

The main issue with a cord and weight balance system is that eventually the cotton cords will begin to fray and tear. When this happens, the sash will no longer glide smoothly, and when the cord breaks, the window won’t be able to stay in a raised position without alternative support, like a stick or rod.

If the cord and weight system for your window are damaged, replacing the window weight ropes is possible, but there are other, more modern options for today’s single and double-hung sash windows.

How Can I Tell if It’s Time to Replace the Window Weight Ropes?

The sash on a single or double-hung window should slide smoothly and easily up and down. It should also remain in position without falling or creeping back into the closed position. If the sash doesn’t remain open or if the window has difficulty sliding up and down, it may be time to replace the window weight ropes.

In order to determine if the window ropes are the issue, you’ll need to remove the jambliner that will likely be made of wood or vinyl — which will be screwed into the window frame — and can be removed by pushing the flanges out from behind the frame and sliding the jamb liner out. Once the jamb liner is removed, you’ll be able to see the balance system and identify the problem area.

After you determine the problem area, contact a professional to order the appropriate replacement parts for your window.

How To Replace Old Window Weight Ropes

1. Remove the part of the jambliner that hides the weight — the jambliner may be wood, vinyl or another material depending on the type and time period of the window. 
2. Remove the damaged rope.
3. Run a new window weight rope over the pulley in the upper part of the window frame and lower it until you can see it in the lower part of the window jamb.
4. Attach the weight to the rope.
5. Repeat these steps on the other side.
6. Pull on the rope until the weight is in its highest position.
7. Line the rope up with the channel in the sash frame and tie a knot in line with the hole or notch in the sash frame meant to secure the rope.
8. Secure the knot to the sash frame with a small nail.
9. Cut any excess rope.
10. Repeat these steps on the other side.
11. Replace the sash frame in the window frame.
12. Replace any pieces of the jamb liner you removed.
13. Test the window.

A Better Alternative for Modern Windows

Rather than using an outdated window rope and weight system, most modern windows use a block-and-tackle window balance system. This system combines a cord and weight system with a spring in a self-contained unit that can be an integrated part of a jamb liner. 

With this system, the tilt pins that allow the sash to tilt out for easy removal also fit into the balance terminal and connect to the block and tackle system. The window weight ropes are part of a pulley and spring system in the jamb liner, so this system is easy to replace and able to handle the weight of a heavier sash.

Replace the Original Cord and Weight System with Fenster’s Jambliners

Here at Fenster, we offer vinyl jamb liners that include a block-and-tackle window balance system that can replace the original cord and weight system. Our kits come fully assembled and include all of the hardware that you’ll need to install them and restore your window back to working order. For more information on how to replace window weight ropes on an old window, you can check out our instructional video. 

Ready to get started? Talk to our professionals at Fenster today to discuss your window repair needs, order parts or request a quote.