Handyman Mike Ferrara shows how to safely replace a cracked window.
- Always wear leather work gloves and safety goggles when working with broken glass.
- Prepare a flat working surface. A portable workbench is recommended.
- To remove the cracked window pane, carefully crisscross masking tape across the glass. Cover the pane with a heavy cloth, then tap gently with a hammer to break away the pieces from the window. This will help prevent splinters from remaining in the frame.
- Before disposing of the broken glass, carefully place it in a heavy duty cardboard box, seal it with duct tape and write, "Caution: broken glass" on the box to prevent injuries. Do not place the box into a receptacle with food to avoid endangering animals that are foraging for food. If animals come around regularly, place the box outside of the receptacle.
- Warm the putty with a hair dryer or blowtorch for a few minutes to make it easier to remove. Scrape away the crumbling remnants with a putty knife.
- Remove any glazier's points with pliers. The glazier points in a window help secure the glass in place. Mark the spots with a pencil for where to insert new points.
- Before installing the new pane, sand and scrape the rabbet (the wooden notch that the pane fits into) with a piece of medium (80 to 100 grit) wood sandpaper. Use a vacuum cleaner to clean up paint chips. Give the rabbet a coat of primer or linseed oil, using a small brush. This will prevent the wood from absorbing the oil in the glazing compound that will be used later to secure the pane.
- To create a cushion for the glass and create a weather-tight joint, squirt a line of paintable latex caulk in the rabbet of the sash before setting in the glass. It's important to use caulk instead of glazing for this step. Caulk isn't as stiff as glazing, which could potentially break the pane when pressed in.
- Use glazier's points with "ears," (available at most home stores) and press them (two along each edge) into the putty with a stiff putty knife. The ears are a support for the back and bottom of the glass when it sits in the pane.
- When measuring for the new pane of glass, it is important to note that a snug-fitting pane can easily crack when the window frame moves or shrinks. The glass should be cut 1/8" smaller than the overall height and width of the actual opening. This will compensate for the glazing compound used to hold the glass in.
- To safely cover the sharp edges of the glass during transport, take an old garden hose and cut out two eight-inch sections. Slit the hose lengthwise, making 2 C-shaped pieces. Slip each end over the top and bottom of the glass pane.
- A good way to carry glass without damaging the pane or injuring yourself is to simply take a six-inch piece of duct tape and fold it so that it creates a T shape with two sticky ends. Press the sticky ends against the glass to create a tab to carry the glass like a handle. Make two T-tabs for greater stability. When the tape is removed, it won't leave any residue.
- Take a handful of glazing compound, and roll it into a rope-like length. Press the "rope" along the joint, and smooth it with your finger along all sides of the pane.
- Use a putty knife to flatten and cut off any excess compound from around the pane. To prevent the compound from sticking to the putty knife's blade, dip it into turpentine, mineral spirits or paint thinner. Once the excess is trimmed, let the compound dry.
