How to replace glass in a window

Necessary tools:
Sash Brush
Putty Knife
Paint Brush
Heat Gun
Caulk Gun

Required Materials:
Wood Sealer
Tube-style Glazing Compound
Sandpaper
Goggles
Gloves
Glazing Points

Estimated Time to Complete:
Beginner: 2 Hours
Intermediate: 1 Hour 15 Minutes
Expert: 45 Minutes

Safety Tips:
Wear gloves and eye protection when removing broken glass from the sashes and when handling or installing the new glass.

Getting Started: Removal of the Glass
For spring-loaded double hung windows, remove them from the wall by pushing against the flexible vinyl channels to release the pins. On older models, the windows may be repaired wile the window remains in the frame.

On newer windows, you will just need to pry out the vinyl glazing strips.

For traditional glazing, you'll want to soften the old putty with a heat gun or a torch. Be careful not to scorch the wood. Then, gently scrape away the soft putty with a putty knife.

Now, it is time to remove the broken glass and metal glazing points from the frame. After they are removed, gently sand the L-shaped grooves to clean old paint and putty. Using a detail sander in place of hand sanding will make the work go faster. If you have any bare wood exposed, coat it with sealer and let it dry.

Reassembly: Installing the New Glass
Apply a thin layer of glazing compound in the primed grooves. Press the new glass lightly to seat it, and press in new glazing points every 10 inches with the top of a putty knife. When installing the glazing points, be sure you're only exerting pressure towards the sash and not onto the glass. Now, apply your glazing compound with your caulking gun. Move the tube tip along the edge of the glass while applying steady pressure to the trigger.

When you've applied it all the way around, smooth the glazing by wetting your finger or a cloth and running it along the bead. You can also smooth the glazing putty with a dampened putty knife.

Finish Touches: Painting
Latex painting can be painted on the same day. Just give it a little time to set first. Overlaping the paint onto the glass by 1/16th of an inch can help to improve the weather seal of the window.