How to Replace Old Window Glazing

Wooden windows can be beautiful with their mullions and many panes. Unfortunately, with this beauty comes the need for maintenance, including replacing old window glazing. Technically "glazing" is the actual glass of the window, though the putty used to seal the panes has come to be known as "window glazing." You may need to re-glaze a window if you have a broken pane or the glazing putty has crumbled. Fortunately, this is something you can do yourself in three steps.

Things You'll Need

• Eye protection
• Gloves
• Heating iron
• Putty knife with 1 inch blade or wood chisel
• Points (optional)
• Sandpaper
• Primer
• Paintbrush
• Cleanser and rag
• Measuring tape
• Glazing putty (in can)

Instructions

1. Put on eye protection and gloves. Remove the old putty. Use a 1-inch putty knife or a chisel to work your way around the inside of the frame. If the putty does not chip away easily, use a heating iron to heat up the putty enough to chip it away with your tool. Take out the metal points that hold in the panes of glass with the putty knife and set them aside. Gently remove the panes of glass.

2. Sand the window frame then clean it thoroughly. Prime the window with the paint of your choice, then paint it. Let the paint dry. If you need to replace some of the panes, measure carefully from the inside corner to diagonal corner and add 1/8 inch. Measure carefully so you don't have to make numerous trips to the hardware store for glass. Buy putty that contains linseed oil. It usually comes in a can.

3. Put a small amount of putty around the lip where the pane of glass sits. Smooth it evenly with your fingers and putty knife. Set the pane of glass on the putty and gently press it in place. Insert the points at the corners, knocking them home with the handle of your putty knife. Roll a length of putty between your fingers and press it around the outside of the pane. Hold the blade of your putty knife at an angle and the handle pointing in the direction you are going, and smooth the putty. Cut away any excess. Repeat for every pane.

Tips & Warnings

• Gloves are recommended when handling glass.

• Use proper precautions when heating old putty

References

• Glass Replacement - How to Replace A Single-Pane Window or Repair Window Glazing
• Repairing Old Wood Windows Step-By-Step