Replacing Broken Glass and Glazing in a Single-Pane Window

Over time, the glazing on windows can harden and crack, and this can cause drafts and result in wind and water leaks. 

If your window glass is also broken, it’s a good time to go ahead and replace the glass and reapply the putty on your single-pane window.  Here is how you can do it:

• Remove the old glass carefully using a cloth over the broken glass and a hammer.
• Remove the old glazing putty with a putty knife. Use a heat gun if necessary.
• Set the new glass in place over a bead of latex caulk. Once the oozing caulk hardens, remove excess with a utility knife.
• Apply the new glazing compound, making sure you do not miss gaps and hollow spots.
• Smooth the glaze using a putty knife dipped in mineral spirits. Dip the knife and repeat as needed until all the glazed surface has been smoothed out.
• Clean off the excess glazing using a putty knife dipped in mineral spirits. Be sure not to touch the smoothed surface.

Check out the full instructions with photographs here.