the painted surface
How To Reglaze or Repair a Window
Traditional wood framed windows exposed to the weather or just because of age will at some time need to be reglazed. The glazing compound or putty holding the glass in the frame becomes brittle, cracks and fails. This failure of the glazing putty can lead to the rotting of the window frame, leakage if rained on and ultimately the need to replace the entire window. Of course we want to avoid these things so occasionally the window will need some maintenance. The term “glazing” technically refers to the pane of glass or the act of installing the panes of glass but the term has become rather generic to also refer to the putty used to seal the window in the frame. This “glazing compound” is a putty like substance formulated to adhere to glass as well as the wood frame. It is sold by several companies and will be labeled as window glazing compound. There is also a “painter's putty” which is similar but not the same, use glazing compound to reglaze a window.
This article is limited to typical maintenance and repair needed during the repainting of home exteriors, not replacing the glass itself. The procedure would be similar except for removing the cracked or broken glass pane and the installation of the new glass pane.
Tools Needed To Repair and Reglaze a Window
Gather the tools needed to complete the job. The tools are fairly common except for the glazing tool. See "Tools" for more information about painting tools. Basically you will need:
- Eye protection and heavy gloves
- Scraper - carbide paint scraper works well, stiff putty knife or 5 in 1 tool
- Sandpaper - 60 to 100 grit
- Single-edge razor blade glass scraper - Careful!
- Vacuum, broom, dust brush or blower
- Exterior primer
- Glazing compound also called glazing putty
- Glaziers points
- Glazier's tool
- Angle sash paint brush
- Exterior oil-based or acrylic primer
- Exterior finish paint
- Glass cleaner
Steps To Take When Repairing, Puttying and Reglazing a Window
Place a drop cloth below the window to catch dust, paint chips and pieces of old glazing.
Wear eye protection and gloves. Bits and pieces of old putty and possibly glass shards will fly around quite a bit during scraping so eye protection is a must. Wear gloves to protect your hands from accidental cuts from the scrapers or glass, especially if you are handling the panes of glass.
Using a stiff putty knife or other type of scraper, scrape out old glazing putty. Use a motion not putting pressure on the pane of glass, it can be easily cracked. A carbide scraper is well worth the cost. It will stay sharp and do a superior job cleaning away the old glazing and peeling paint. The carbide scraper works well on the wood portions leaving a good surface to sand and prime. In some cases much of the old putty will fall out once you begn scraping. Remove as much as possible.
During scraping some of the glazier points may fall out. These or new ones should be replaced to help secure the pane of glass in the window. To install the glazier points use a stiff putty knife to push them into the window frame. Be careful to push in the direction of the wood amd not the glass to prevent cracking the pane. The points shown in the photo are common ones and are shaped to allow easy installation. There are some glazier points that are flat three-sided pieces of metal which are much more difficult to use.
Once the loose putty is removed there will be some that is still adhered to either the glass or the wood but not both. Using your judgement some of this can be removed with more work. Or the spaces can be filled later with glazing putty during the reglazing step.