Original or old sash windows usually contain two counter balancing weights suspended on cords. These hang inside the frame on either side of the window and help to make the window easier to open. Over time the cord can often wear out and snap, dropping the weights to the bottom of the frame. This will result in a window that is difficult to open and that won’t run smoothly in the frame runners. Replacing the cords is not the easiest task, but it can be done, and done for far less money than it would cost a professional to fix.
When replacing one broken sash cord, it is usually best to replace them all. This will mean that all of the cords are in perfect condition and that you won’t be repeating the process all over again in a few months when another old cord snaps. Either buy cord that is specifically made for the job or try to match the old cord as closely as possible, preferably with waxed cotton cord.
Step 1 – Removing the inner sash
Looking at the window from inside the house, you should see that the inner sash is guided and held in place by two strips of beading. Using a filling knife or flat-head screwdriver, prise off the beading strips, being careful not to crack or split the wood. If the window has been painted numerous times, you may need to cut through the paint with a sharp blade. Cut through any unbroken cord still attached to the inner sash and then lift it out of the frame.
Step 2 – Removing the weights
You can now gain access to the inner weight compartments on either side of the frame. There should be weight covers (small sections of the frame that pop open) at the bottom of the frame, inside the track where the sash ran. Again, if the frame has been painted a lot, you may need to cut through some paint to get these open. You can then lift the dropped weights out of the frame.
Step 3 – Removing the outer sash
Remove the beading between the two sashes and cut through any unbroken cord. You will now be able to lift the outer sash out of the frame. Remove all of the old cord by prising it off the sashes and cutting it off the weights.
Step 4 – Fitting new cords
Starting with the outer (or upper) sash, cord and weight, hold one end of the cord and feed the other end over the pulley wheel and down into the frame. When enough cord has been fed in, you should be able to grab the end through the open weight covers at the bottom. Pull the cord through and tie it tightly to the first weight. Repeat the process on the opposite side of the frame.
Step 5 – Replacing the outer sash
To get the correct length on the cords, the sash should be about 10cm above the windowsill when the weight reaches the top of the weight compartment. Either ask someone to help by holding the sash at that position, or prop the sash in place with the 10cm gap. Pull the cord to lift the weight until you hear it touch the pulley wheel. Nail the cord into position in the cord groove on the upper sash and then trim any excess cord. Repeat on the opposite side of the frame before replacing the central beading.
Step 6 – Replacing the inner sash
Attach the new cord to both cord grooves on the inner sash with nails. Rest the sash on the window sill and feed the cord over the pulley wheels and down into the weight channel within the window frame. You may need some help to hold the sash while you tie the cord tightly to the weights. The cord length is correct if the sash weight hits the top of the channel when the sash is fully down. Replace the weight covers carefully, ensuring that they are completely flush with the frame. If you fail to do this, the sashes may not run smoothly in their frames. Hold the inner sash in place and replace the beading that holds it.