01 of 08
Make Sure You Have the Right Type of Window
Broken windows sometimes require an expensive repair call from a glazier--or worse, an even more expensive visit from a replacement window company to replace the entire sash. As it turns out, it's easy and inexpensive to do this yourself. You just need a few simple tools and materials, some of which you may already have on hand.
Note: The procedure shown here works on older, single-pane, unsealed glass windows. If you have an older (pre-1950s or 60s) house that hasn't been updated, you might... have this kind of window. Or you might have one in a shed, outbuilding, workshop, etc. If you have double- or triple-pane windows (often called thermal or insulated windows), you'll have to have the glass replaced by a professional, or you can remove the entire sash and replace it with a new sash.
Continue to 2 of 8 below.
- Thick leather work gloves
- Safety glasses
- Putty knife
- Wood chisel or razor scraper
- Fine-grit sandpaper
- Linseed oil or clear wood sealer
- Tape measure
- Replacement glass
- Pencil (optional)
- Metal straightedge (optional)
- Glass cutter (optional)
- Glazier's points
- Glazing compound (putty)
- Exterior-grade paint
02 of 08
How to Fix a Broken Window: Step 1
First, understand how a window pane is fastened into the frame. Under the visible glazing compound (which is usually painted) are glazier's points that have been tapped into the frame. These tiny metal triangles are basically like "nails" that hold the glass to the wood.
Using a putty knife, pry up the glazing compound. It should come off in large chunks. Then, use the putty knife, pliers, or a thin flat-head screwdriver to remove the glazier's points. Wearing thick gloves (leather... recommended), remove all of the broken glass.
Continue to 3 of 8 below.
03 of 08
How to Fix a Broken Window: Step 2
Using a chisel or razor scraper, scrape down the section of the frame (the "L-channel") from which you removed the compound and glazier's points. Be careful not to gouge the wood. Sand the wood smooth with fine-grit sandpaper, then seal any bare wood with linseed oil or clear wood sealer applied with a paintbrush.
Continue to 4 of 8 below.
04 of 08
How to Fix a Broken Window: Step 3
Now it's time to measure and cut the new window glass to size. You can have the glass cut for you at a hardware store or home center, or you can cut it yourself with a simple glass cutter.
Measure the width and height of the window opening, using a tape measure and measuring to the outside edges of the L-channels. Subtract 1/8" from each measurement to use as the glass size.
To cut the glass yourself, place it on a clean, flat work surface. Make marks for the cutting line with a pencil or... permanent marker. Place a metal straightedge on the marks, and score the cutting line onto the glass with a glass cutter. A glass cutter has a small metal wheel for scoring the glass. Run the cutter along the straightedge while pressing the wheel down firmly. Make only one pass with the cutter.
Continue to 5 of 8 below.
05 of 08
How to Fix a Broken Window: Step 4
Be sure to wear safety glasses and gloves for this step. Slide the glass along your work surface so that the scribed line on the glass is aligned with the edge of the surface. Holding the main portion of the glass with one hand, use the other hand to push down sharply on the "waste" portion of the glass to snap it along the scored line.
Continue to 6 of 8 below.
06 of 08
How to Fix a Broken Window: Step 5
Roll out the glazing putty into long, thin "ropes." Push the ropes into each L-channel of the window frame where the glass will rest. Place the glass into the frame, resting it in the putty. Using your putty knife, push two glazier's points into the bottom of the frame. If you need extra force, gently tap the handle of the putty knife with a rubber mallet to drive in the points.
Continue to 7 of 8 below.
07 of 08
How to Fix a Broken Window: Step 6
Install additional glazier's points, two per side for a total of eight per window pane. Roll more glazing compound between your hands into thin ropes and force these ropes into each side of the frame. Force the rope farther into the L-channel with your putty knife held at a 45-degree angle.
Continue to 8 of 8 below.
08 of 08
How to Fix a Broken Window: Step 7
Let the glazing compound dry and harden, following the manufacturer's recommended drying time. Paint the putty and any exposed wood with exterior-grade paint.