2–3 hours total (spread over two days due to curing).
If you have a basic toolbox and patience, the DIY route is overwhelmingly worth it. The skill is easy to learn, and the satisfaction of repairing rather than replacing is genuine. Part 7: Final Review – Is This Guide Accurate? Having followed nearly identical steps on a drafty cellar window and a decorative casement, I can confirm the method works beautifully. The only variable is the condition of the old putty—if it’s pre-1970s and rock-hard, budget an extra hour for removal. Also, do not use this method on double-pane, argon-filled, or vinyl-framed windows; those are sealed units requiring replacement. how to repair a broken window pane
Inspect for rot. If the wood is soft, dig out the rot and apply wood hardener or epoxy filler. Let it cure fully before proceeding. Step 4: Measure for New Glass Measure the height and width of the rabbet opening at three points each (top, middle, bottom for width; left, middle, right for height). Use the smallest measurement. Subtract 1/8” from both dimensions to allow for expansion. For example, if your smallest width is 24”, order glass at 23-7/8”. For hardware store cutting, bring your measurements. Tempered glass is not needed for most residential windows—standard 1/8” (3mm) single-strength glass works for panes up to 10 sq ft; 3/16” (5mm) for larger. Step 5: Apply a Bed of Putty (Bedding Compound) Before inserting glass, roll a thin rope of glazing putty (about 3/8” thick) and press it into the rabbet’s inner corner. This creates a cushion and seals the back of the glass. If using latex glazing, you may skip this step (check label). For oil-based putty, brush a thin coat of linseed oil on the bare wood first to prevent the wood from sucking out the oil in the putty. Step 6: Set the New Glass Carefully place the glass into the frame, pressing gently against the putty bed. Use a suction cup if available. The glass should sit evenly with a slight gap all around. Ensure it is flush with the front edge of the frame (not protruding). Step 7: Insert Glazing Points Push glazing points into the frame every 6–8 inches around the perimeter. Use the putty knife to push them flush—slide the knife along the glass, press the point into the wood with the blade. Do not hammer directly; use the knife as a lever. Points should sit flat against the glass, not above it. Step 8: Apply the Front Putty (Face Glazing) Knead your putty until pliable. Roll into a rope slightly thicker than your finger. Press it firmly along the glass-to-frame junction, angling the putty to form a neat bevel (about 45 degrees). Smooth with a putty knife dipped in water or linseed oil (prevents sticking). Wipe away excess from the glass with a rag. 2–3 hours total (spread over two days due to curing)
Breaking a window pane is one of those household moments that triggers an immediate sigh. Whether it’s a stray baseball, a slammed door, or simple age-related cracking, the sight of shattered glass is never welcome. However, before you call a glazier and spend $150–$300, it’s worth knowing that repairing a standard single-pane window is a surprisingly achievable DIY project. After recently restoring a cracked sash window in a 1920s bungalow, I’ve compiled this exhaustive review of the process—warts and all. Part 1: Initial Assessment – Can You Repair It? Not every broken window is a candidate for DIY repair. Double-glazed (insulated) units with a failed seal or shattered inner pane generally require a full replacement unit from a manufacturer. However, traditional single-pane windows—common in older homes, garages, sheds, and some modern wooden frames—are perfect for this task. Part 7: Final Review – Is This Guide Accurate
Deducting half a star only because the curing time for oil putty feels endless when rain is forecast. Otherwise, it’s a near-perfect DIY repair that saves money, extends the life of your windows, and keeps one more piece of trash out of a landfill. Final tip: Buy a small glass cutter and practice on an old picture frame. Once you can cut your own glass, the cost drops to pennies per repair. Good luck, and watch those fingers.
2–3 hours total (spread over two days due to curing).
If you have a basic toolbox and patience, the DIY route is overwhelmingly worth it. The skill is easy to learn, and the satisfaction of repairing rather than replacing is genuine. Part 7: Final Review – Is This Guide Accurate? Having followed nearly identical steps on a drafty cellar window and a decorative casement, I can confirm the method works beautifully. The only variable is the condition of the old putty—if it’s pre-1970s and rock-hard, budget an extra hour for removal. Also, do not use this method on double-pane, argon-filled, or vinyl-framed windows; those are sealed units requiring replacement.
Inspect for rot. If the wood is soft, dig out the rot and apply wood hardener or epoxy filler. Let it cure fully before proceeding. Step 4: Measure for New Glass Measure the height and width of the rabbet opening at three points each (top, middle, bottom for width; left, middle, right for height). Use the smallest measurement. Subtract 1/8” from both dimensions to allow for expansion. For example, if your smallest width is 24”, order glass at 23-7/8”. For hardware store cutting, bring your measurements. Tempered glass is not needed for most residential windows—standard 1/8” (3mm) single-strength glass works for panes up to 10 sq ft; 3/16” (5mm) for larger. Step 5: Apply a Bed of Putty (Bedding Compound) Before inserting glass, roll a thin rope of glazing putty (about 3/8” thick) and press it into the rabbet’s inner corner. This creates a cushion and seals the back of the glass. If using latex glazing, you may skip this step (check label). For oil-based putty, brush a thin coat of linseed oil on the bare wood first to prevent the wood from sucking out the oil in the putty. Step 6: Set the New Glass Carefully place the glass into the frame, pressing gently against the putty bed. Use a suction cup if available. The glass should sit evenly with a slight gap all around. Ensure it is flush with the front edge of the frame (not protruding). Step 7: Insert Glazing Points Push glazing points into the frame every 6–8 inches around the perimeter. Use the putty knife to push them flush—slide the knife along the glass, press the point into the wood with the blade. Do not hammer directly; use the knife as a lever. Points should sit flat against the glass, not above it. Step 8: Apply the Front Putty (Face Glazing) Knead your putty until pliable. Roll into a rope slightly thicker than your finger. Press it firmly along the glass-to-frame junction, angling the putty to form a neat bevel (about 45 degrees). Smooth with a putty knife dipped in water or linseed oil (prevents sticking). Wipe away excess from the glass with a rag.
Breaking a window pane is one of those household moments that triggers an immediate sigh. Whether it’s a stray baseball, a slammed door, or simple age-related cracking, the sight of shattered glass is never welcome. However, before you call a glazier and spend $150–$300, it’s worth knowing that repairing a standard single-pane window is a surprisingly achievable DIY project. After recently restoring a cracked sash window in a 1920s bungalow, I’ve compiled this exhaustive review of the process—warts and all. Part 1: Initial Assessment – Can You Repair It? Not every broken window is a candidate for DIY repair. Double-glazed (insulated) units with a failed seal or shattered inner pane generally require a full replacement unit from a manufacturer. However, traditional single-pane windows—common in older homes, garages, sheds, and some modern wooden frames—are perfect for this task.
Deducting half a star only because the curing time for oil putty feels endless when rain is forecast. Otherwise, it’s a near-perfect DIY repair that saves money, extends the life of your windows, and keeps one more piece of trash out of a landfill. Final tip: Buy a small glass cutter and practice on an old picture frame. Once you can cut your own glass, the cost drops to pennies per repair. Good luck, and watch those fingers.