Replace window sash cords when the cords fray and break; or repair sash cords if they become disconnected from the weights that give balance to the window. Some windows have chains instead of ropes and they, too, can break. The process of fixing chains is the same as with ropes.
Sash cords help sashes stay open (without a stick to prop it up), move up and down easily, and close properly. Old double-hung windows have sash cords; new and replacement windows are cordless.
Gather your materials: Lubricant, utility knife, stiff putty knife, hammer, new window cord roping, and screwdriver.
Look for a spray lubricant like WD-40 or something similar.
Access the window sash cords.
Remove the window and then open the panel cover on the side jambs to access the sash cord, weight and pulley. For a window without access panels, you also need to remove the window casing.
Lubricate the pulleys.
Clean them first if they look like they need it.
Tape the ends of the new cord to the old cord.
Taping the new cord to the old cord will help you feed it through the pulley.
Pull the old cords out of the access panel and remove them from the new cords.
When you pull the old cords out the new cord will feed up and over the pulleys.
Feed the cords through the hole in the weights and tie a knot.
Tie the knot to securely hold the weight into place. If using chains, use wires to secure the ends to the weights.
Put the weights back in the jamb.
Slide the weight back through the access panel.
Test the new cords by pulling the weights up to the pulleys.
You want to ensure that the cords and weights operate smoothly.
Put the upper sash in.
Slide the upper sash back into place.
Place the lower sash on the windowsill and cut each cord 3 inches below the hole on each side.
Hold each cord firmly against the window to measure the 3 inches. Cut the cord 3 inches below the place where the cords attach to the sides of the lower sash.
Reinsert the cords in the sides of the lower sashes.
Tie a knot in the ends of the cords and reinsert them in the slots and holes on the sides of the lower sashes.
Put the lower sash back into the window frame.
Slide the lower sash back into the window frame.
Replace the window trim and access panels.
Finish putting the window pieces back into place.
