How to Renovate Older Homes: Repairing Sash Cords and Weights
If you have an old house, then you will be familiar with sash cords and weights to older windows. You will know that you have sash windows because they have a tendency to crash down or rise slowly when not locked. When sash windows are broken or have the wrong size weights attached to them, this is a major problem and they need to be replaced.
This is not a job to take lightly or alone. Replacing weights is a two-person job and it will require re-painting of the windows afterwards. This is because the individual sashes must be removed and they are very heavy and awkward to handle. So allow plenty of time for this job that will include painting. It is important to remember that after you have repaired and begin to paint, do not get paint on the new sash cords or you will find yourself either repeating this chore.
Buying Replacement
You need to check the size and type of sash cord that you’ll need to replace the damaged ones. A good rule of thumb is to take a piece of the original cord with you. The weights should balance exactly the weight of the window, which includes the glass. If the original glass has been replaced than the existing weights cannot be the correct size and need to be replaced. You can purchase these on-line but I would not suggest it unless you know exactly the size and weight that you are looking for. Replacements are sold at larger hardware stores and at builders’ supply stores.
Removing Sash Cords
Before removing the inner stop molding on each frame side, run a utility knife between the molding and the frame to break the skin of the paint. Some of these sash cords may have been in place for many years without being replaced so this part may take some time. Pry off the molding with an old chisel, starting from the center. Don’t worry about destroying the molding in the process (as it will happen). Just buy replacement molding at the local hardware store or lumberyard.
Pull the top edge of the bottom sash away from the frame. Cut through any remaining sash cord with a utility knife. Tie a length of string to the cord attached to the weight and gently lower it to the bottom of its box. Now remove the bottom sash from the frame.
Before removing the top sash, pry out the parting stop that divides the two sashes from each side of the frame, starting at the bottom of the frame. Lower the top sash; cut the cords and lower the weights as you did before. Remove the sash from the frame.
Now unscrew the cover of the weight boxes at the bottom of each side of frame. Carefully fit each weight up slightly before pulling it out. Make a sketch of how the weights are tied to the cords (this will definitely come in handy later).
Work out how much sash cord you need. You can use the old one as a guide. When the window is in its lowered position, the weight should not quite reach the top, in the upper position, the weight should not quite reach the top; in the upper position, the weight should be just above the bottom of its box. Attach a length of string to the new cord.
Starting with the outer sash, feed the cord through the pulley and down inside the box. Pull the cord through and thread it through the weight; tie it in into as previously noted. Then return the weight to its box, and screw the cover back in place.
After you’ve replaced the outer sash window, then replace the old parting stops or cut new ones to length and push them into place on both sides of the frame. Fasten the stops to the frame with finishing nails, and use a nail set to drive them below the surface.
Then fit the inner sash; pull the weights until they are just below the top of the their boxes. Hold the sash in its lower position, place the cords in the groove at each side of the sash, and fasten them with box nails. If needed, cut off the cords at the grooves. Then fit the sash into the frame; replace the stop molding, using brads.
Now paint!
Sources:
Repair and Restoration by Tony Wilkins
Upgrading and Repairing Windows by Scott Mueller and Briank Knittel
