How To Re-Glaze A Window

Glazing a WindowIf you’ve noticed your windows looking a bit unsightly, or if the outside elements have started to creep inside your home, then it may be beneficial to learn how to re-glaze a window. Water or outside air can find its way through cracks and small openings if your windows are not properly glazed. Glazing is the putty that seals the small areas between the glass window panes and the interior wooden frame (the sash and muntins). Re-glazing a window is inexpensive and easy enough to accomplish in an afternoon.

Uninstalling And Preparing The Window

To begin, remove the window sash from the framing and place it on a workbench. Uninstalling the sash typically involves removing several screws holding it in place to the jambs and casing, and can vary based on the type of window, according to This Old House. While it is possible to re-glaze a window while it is still installed and operable, attempting this is not recommended unless you have experience doing so. Re-glazing a window while it is still in the casing can be dangerous and difficult because of the awkward angles at which you must work.

Once the window sash has been uninstalled and laid on a workbench, begin removing the old glazing. A putty knife or other type of scraper should do the trick; you may use a razor if the old glazing is particularly difficult to remove. Be careful not to apply too much pressure, or you may break the glass or chip away at the paint on the sash. If the glazing is too difficult to remove at room temperature, you may use a heat gun to soften the material. If you do end up using a heat gun, this will damage the surrounding paint. At this point you should sand, scrape, and re-paint the entire window (which you may want to do anyway since you’ve already removed the sash from the frame). It may indeed be a good idea to plan to paint the entire window, since you will have to paint the glazing at the very end of the re-glazing process, according to Do It Yourself.

Next, clean the surface of the window. The goal is to remove dirt or glazing debris left on the surface so that the new glazing will properly adhere to the pane. Priming the wooden sash after scraping is optional. Some choose to do this, though it’s not necessary, as oils in the new glazing alone can act as a sufficient primer.

Installing Glazier Points And Applying the New Glazing

You may inadvertently have removed the old points during the scraping process, and that’s OK. If you didn’t remove the old glazier points during scraping, then you should do so now and replace them with new ones. This ensures that the glass pane stays secured in the window. Install one new glazier point in the middle of each side of the sash. For a typical four-sided sash, this means installing four glazier points.

Now you’re ready to apply the new glazing to the window. Take a small ball of glazing and roll it into a rope about ½ inch in diameter. Match the length of the rope to the length of the window side that you’re applying it to, then press it into the edge of the glass and sash with your fingers or the flat edge of your putty knife. You don’t need to apply too much pressure initially, as this is just to put the glazing in place. Then take the putty knife and shape the glazing at a clean angle from the sash to pane. The precise angle at which to do this is not too important. Take a look at the glazing on another window to get an idea of the angle used. The main point is to seal the gap and make it look neat.

You will undoubtedly have some excess glazing that you’ll need to trim from the glass pane. Use the putting knife and cut a clean line along the plane, parallel to the sash. Neaten up any corners so that the glazing is even.

Final Steps

Once you’ve finished re-glazing the window, reinstall it to the casing. Before you paint the glazing, you need to wait for it to cure. Check for information on the glazing container to see how long you need to wait (usually about a week). Once it’s ready, paint over the new glazing to match the color on the sash. You’re done! Your new glazing is visually appealing, and helps protect against the elements. Learning how to re-glaze a window is a simple, satisfying project that just about anyone can accomplish.

Related Resource: Window Sash