How to Repair Single Pane Windows

Single-pane windows require special care and attention in maintenance and repairs. Read on for instructions on how to properly repair, replace, and glaze these windows.

Unlike double-pane windows, single-pane windows must be glazed and installed carefully to achieve a tight fit. Cracked window panes, loose panes, or cracked glazing all require repairs.

Replacing Cracked or Broken Windows

Replacing single-pane windows isn't as simple as just putting in a new pane of glass; there are several steps you must take to ensure that the window seals fully.

First, you need to remove the old panes of glass and scrape out all traces of old glazing and putty with a chisel or a stiff, one-inch putty knife. Until all of the old glazing is gone, there won't be room for a new window pane to fit inside the frame.

Once the window frame is clear, repaint the frame using oil-based paint. Repainting is necessary because you're likely to scrape off the old paint while removing old putty and glazing, and it also provides the right kind of surface to ensure your new glazing sticks. If you don't intend to repaint, wipe the surface down with linseed oil or kerosene to keep the dry wood from sucking all the oil out of the glazing compound.

Glazing Single-Pane Windows

You can obtain custom-sized glass from any glass shop or home repair store. Lay the glass in the window frame and apply glazier's points every four to six inches to hold it in place. Warm small amounts of glazing compound into ropes about a quarter inch in diameter, and stick them firmly into place along the edges of the pane.

With a putty knife or glazier's tool held at a 45 degree angle, tamp the glaze down, tightly sealing the window into the frame. If necessary, use linseed oil or turpentine on the blade to prevent the glazing from sticking to it. If you'd like, you can retouch the glazing with paint a few days later.