Glazing A Single Pane Window
If properly maintained, single pane windows can last for a hundred years or more! We present some tips on how to preserve your windows and keep them free from the draft by replacing old glazing putty.
Step 1: Remove The Old Putty
First, pull out loosed pieces of the glazing compound with a putty knife. Ease the remaining areas with a heat gun and carefully scrape the putty away.
The glass on the older single-pane windows is usually surrounded by glazing compound putty, which holds the glass and place and keeps weather away. The glazing putty often lasts for as much as several decades, but as the years go by it becomes solid, cracks and begin to fall off the window.
When there is a missing compound or if the compound is loose, wind and rain leak is let in around the window. It takes around 15 minutes to an hour to replace the putty around one pane of glass- the time depends largely on the size of the pane and also the stubbornness of the old putty. It is advisable to also replace broken glass while replacing the old putty.
It’s attainable to replace the glass and putty with the window still in place, but your time will be saved, and you can get better results if you can remove the window and fasten it down on a flat surface.
If there is any broken glass, clear it out of the way before removing the old putty. Remember to put on heavy gloves and eye protection. Place a cloth over the broken pane and tap it gently with a hammer. With the glass broken up, pull the fragments out of the window frame by hand. Remove the old glazing points with pliers. If the old glass is still in good shape, there is no need breaking it; leave it in place.
The next step is to remove the old putty. If the putty is broken badly, you can take away large fragments quickly to save time. Putty that is in good condition usually takes longer to remove. With your heat gun in one hand and a putty knife in the other, heat the putty to make it soft and scratch it out. To protect your hands from burns, make sure you wear leather gloves. Also, make sure you keep moving the heat gun around to avoid focusing heat on one area; otherwise, the heat will crack and destroy the glass.
Step 2: Replace The Glass And Putty The Window
Step two is to set the new glass onto a bead of liquid fill. Ensure you press the glazing points into the wood, and let the excess fill that comes out under the glass harden and then slice off later using a utility knife.
If there is a need for a new glass, measure the opening of the glass, subtract 1/8 inches from your measurement and visit a full-service hardware store to cut the new glass to size. Take a fragment of the old glass with you so you can match the thickness of the old glass. Additionally, buy a package of glazing points to hold the glass together while the new compound softens and hardens. Glazing compounds are usually available in liquid/acrylic and oil-based types. The liquid products, which come in a tube, have a longer expectancy and there is no need to wait days for them to dry before painting them.
For the fitting of the new glass, the instructions on the glazing compound may tell you to place a light dip of compound inside the frame and then set the glass on it. This works well with the soft liquid compound. But if you’re using oil-based compound, place in a light bead of acrylic latex fill instead. Set the glass onto the fill, then shake and press down to firmly insert the glass.
For the job to be complete, flatten out the new glazing compound. Oil-based putty is usually easier to work with when it’s warm and not when it’s cold and hardened. To heat the putty, set the can in a vessel of hot water for a few minutes. Remember: all oil-based putty remains soft for several days, so you must be careful not to touch it after the smoothing.