The most common repair that needs to be done on a sash window is replacing the cord. Over time it will get worn and tangled, potentially leaving you with windows that operate less efficiently than they once did. Fortunately you can have the cord replaced and restore your sashes back to their best.

Replacing the cord in a sash window can be a major job, especially if you need to replace it in both the upper and lower sashes. When you start you’ll have to remove the beads from the inside of the frame first. You must take care with these to ensure you don’t damage them, unless you are planning on replacing them as part of the restoration.

Once the beads are removed from each side of the frame, you need to use string to make it easier to thread the new cord when you come around to it. If the cord has snapped attach the string just below the break so you can feed it through the pulley. If it is not broken tie the string as close to the pulley as you can then cut beneath it. After this is done you can remove the lower sash.

Next you need to remove the parting beads from their grooves. These could have been wedged in place or may be screwed or nailed to hold them there. After this is done you can remove the upper sash if you are replacing the cord in it (if you aren’t you can leave it alone).

You are ready now to remove the pocket cover from each side of the frame so you can get access to the weights. This should be a simple task unless the covers have been nailed or screwed in place. Once you finish remove the weights and get rid of the old cord.

Now you are ready to replace the cord itself. The new cords should already be cut to a suitable length, generally one and a half times the depth of the sash window. You need to tie them to the string you fed through the pulley earlier, this makes it easier to thread it through the compartment. When this is done you simply pull the string until the cord come out of the pocket.

After the cord is in place you simply remove the string and re-attach the weight. It should have a hole in it for the cord to thread through. Once you do this tie a stop knot to hold it in place and tuck the end of the cord into the cavity at the top of the weight to secure it. The final step is to replace the weights into the pocket and put the covers back on. The cord is now replaced and you just have to reassemble the window.

The first part of the assembly is to replace the parting beads. After this is done you can put the upper sash back in the frame. Next you should put the lower sash on the sill so you can secure the cord in place. You need to raise the weights to their highest point and tie knots in the cords in line with the knot holes. In some cases you may need to nail the cord in place to secure it. When this is done you can cut off the excess and put the lower sash back in place. The final step is to replace the staff beads.

The process involves many stages and can take a little time. If you would rather have an experienced specialist carry out the restoration for you rather than taking it on yourself you can contact David Humble. We specialise in professional sash window restoration throughout Northumberland, providing a complete and detailed service.