Sixteen Simple Steps to Replace a Broken Window Pane in a Wood Frame

If you have a cracked or broken window pane in a wood frame, follow these 16 steps to replace the glass.

1. Make sure you have these tools: blue painter's tape, long nosed pliers, heat gun or chisel, putty knife, tape measure, linseed oil, small paint brush, replacement glass, glazier points, glazing compound, paint.
2. Put on safety glasses or goggles. Keep heavy duty work gloves nearby; you will need them before starting step seven. Bring a garbage can or other receptacle for the broken window pane to the work area.
3. Create a grid of blue painter's tape over the broken window pane, spacing the tape strips about six inches apart in both directions. The tape with help you safely to remove the glass later.
4. If the window pane to be replaced is on the ground floor and easily accessible, you can leave the sash in the frame. In this case, work from the outside of the window. Proceed to step 4.
5. If the glass to be replaced is in a second story or higher window, or if the window is difficult to reach, work from inside. You will need to remove the sash from the window frame. To do this, use a utility knife to cut the paint between the window stop and the frame and the sill. Remove the stop; then remove the sash. Place the window sash, outside up, on a stable, flat surface.
6. Use a heat gun or a chisel to remove the glazing compound from around the edges of the window pane.
7. Remove the glazier points that you will find under the glazing compound using a long nosed pliers.
8. Put on your heavy duty work gloves, and pull the window pane away from the sash, using the break or crack as a leverage point. The painter's tape will help hold the glass together as you remove it. Be careful when removing the glass. Place it directly in the garbage receptacle.
9. Using a putty knife, remove all debris from around the inside edges of the sash.
10. Make sure the sash opening is square by comparing the measurements of the two diagonals from top left to bottom right, and from top right to bottom left. If these measurements are the same, your window is square. If they are not, you will need to square the opening by adding shims, or planing the sash.
11. Measure the height and width of the opening, then subtract one-eighth inch from both dimensions to purchase replacement glass that will fit the opening.
12. Coat the inner sash edges with linseed oil using the small paint brush to help keep the glazing compound from drying.
13. Shape a rope of glazing compound into a rope about one-eighth of an inch thick and the same length as the side of the opening. Pat into place with your fingers. Do the same for all four edges, then lay on the replacement window pane.
14. Insert glazier points between the glass and the sash about every ten inches, using the putty knife to slide the pins into the sash.
15. Repeat step 13, using three-fourth inch thick ropes of glazing compound. Bevel the compound using the putty knife held at a 45 degree angle from the window pane.
16. Allow the glazing compound to dry overnight; then paint it to match the sash. If the sash was removed from the frame, replace it and the window stops.