DIY Guide: How to Fix a Broken Window and Restore Your View

A broken window is more than just an eyesore; it’s a security risk, an energy drain, and a potential hazard. Ignoring a cracked or shattered pane can lead to higher energy bills, drafts, insect infestations, and even water damage. Fortunately, replacing a broken window is often a manageable DIY project, saving you money and giving you a satisfying sense of accomplishment. This comprehensive guide provides step-by-step instructions on how to fix a broken window safely and effectively.

Assessing the Damage and Gathering Supplies

Before you begin, take a good look at the damage. Is it a simple crack, a shattered pane, or damage to the window frame itself? This will determine the scope of the project. For most broken panes, you’ll need the following supplies:

• Safety Glasses: Essential for protecting your eyes from flying glass shards.
• Heavy-Duty Gloves: To protect your hands from cuts.
• Putty Knife or Scraper: For removing old putty.
• Chisel (Optional): For stubborn putty removal.
• Hammer: For gently tapping the chisel or glazing points.
• Glazing Points: Small metal triangles that hold the glass in place.
• Linseed Oil Primer: To prepare the frame for new putty.
• Glazing Putty: A compound used to seal the glass to the frame. Choose a high-quality putty that is paintable.
• Measuring Tape: For accurately measuring the window opening.
• New Glass Pane: Order the correct size and type of glass (single-pane, double-pane, tempered, etc.) from a glass supplier.
• Heat Gun or Hair Dryer (Optional): Can help soften old, hardened putty.
• Drop Cloth or Plastic Sheeting: To protect the floor and surrounding area.
• Small Container: To keep putty workable.
• Stiff Brush: For cleaning the frame.
• Pencil or Marker: For marking the glass.
• Caulk (Optional): For sealing the exterior of the window frame (especially for exterior windows).
• Caulk Gun (Optional): If using caulk.
• Vacuum Cleaner: For cleaning up glass shards.
• Dustpan and Brush: For sweeping up debris.
• Sealant Remover or Mineral Spirits (Optional): For removing old sealant or putty residue.

Safety First: Preparing the Work Area

Safety is paramount when dealing with broken glass. Before starting any work, take these precautions:

• Wear safety glasses and heavy-duty gloves at all times. Even small shards of glass can cause serious injuries.
• Clear the area of any obstacles. Move furniture and anything else that might get in the way.
• Lay down a drop cloth or plastic sheeting to protect the floor from glass shards and putty.
• Ventilate the room. Working with putty and primer can release fumes, so open a window or door for ventilation.
• Keep children and pets away from the work area.

Step 1: Removing the Broken Glass

This is the most delicate and potentially dangerous part of the process. Take your time and be extremely careful.

1. Carefully remove any large pieces of glass. Use your gloved hands to gently pull out any large, loose shards. Dispose of them immediately in a sturdy container lined with heavy-duty plastic.
2. Remove smaller glass shards. Use pliers or a utility knife to remove smaller pieces that are embedded in the putty. Again, dispose of them carefully.
3. Vacuum up any remaining glass fragments. Thoroughly vacuum the entire area, including the window frame, sill, and surrounding floor. Pay close attention to corners and crevices.

Step 2: Removing the Old Putty

Old putty can be incredibly hard and difficult to remove. Here’s how to tackle it:

1. Soften the putty (Optional). If the putty is very hard, use a heat gun or hair dryer to soften it. Apply heat evenly and carefully, avoiding overheating the glass or frame. Be extremely cautious when using a heat gun; it can easily damage wood and other materials. A heat gun on low is sufficient.
2. Use a putty knife or scraper. Insert the putty knife or scraper between the putty and the glass, angling it slightly to avoid scratching the frame. Gently tap the back of the knife with a hammer to help it penetrate the putty.
3. Carefully pry away the putty. Work your way around the window frame, carefully prying away the putty in small sections. Be patient and avoid using excessive force, which could damage the frame.
4. Use a chisel (Optional). For stubborn areas, use a chisel to carefully chip away the putty. Hold the chisel at a low angle and tap it gently with a hammer.
5. Remove the glazing points. Once the putty is removed, you’ll see small metal triangles (glazing points) holding the glass in place. Use pliers or the tip of your putty knife to carefully remove them. They might be embedded in the frame, so be gentle.
6. Clean the frame. Use a stiff brush to remove any remaining putty residue, dirt, or debris from the frame. You can also use mineral spirits or a sealant remover to clean the frame thoroughly.

Step 3: Preparing the Frame

A clean and properly prepared frame is essential for a good seal and a long-lasting repair.

1. Inspect the frame for damage. Look for any signs of rot, decay, or insect damage. If you find any significant damage, you may need to repair or replace the frame before installing the new glass.
2. Sand the frame (Optional). If the frame is rough or uneven, sand it lightly with fine-grit sandpaper to create a smooth surface for the putty to adhere to.
3. Apply linseed oil primer. Apply a thin, even coat of linseed oil primer to the frame where the putty will be applied. This will help the putty adhere to the frame and prevent it from drying out and cracking. Allow the primer to dry completely according to the manufacturer’s instructions. Typically, this is a few hours.

Step 4: Installing the New Glass

Now it’s time to put the new glass in place.

1. Measure the opening accurately. Double-check your measurements to ensure that the new glass pane is the correct size. It should fit snugly but not be too tight. Subtract about 1/8 inch from both the length and width to allow for expansion and contraction.
2. Apply a bead of putty. Roll a rope of putty about 1/2 inch thick and press it firmly around the perimeter of the frame where the glass will sit. This bed of putty will provide a cushion for the glass and help create a watertight seal.
3. Carefully position the glass. Gently place the new glass pane into the frame, centering it over the putty. Press down lightly to ensure that it is seated evenly.
4. Secure the glass with glazing points. Insert glazing points into the frame around the perimeter of the glass, spacing them about 4-6 inches apart. Use a putty knife or pliers to push the glazing points into the wood until they are flush with the surface. The number of glazing points needed depends on the size of the window. Larger windows will require more glazing points.

Step 5: Applying the Glazing Putty

This is the final step in sealing the glass to the frame.

1. Knead the putty. Knead the glazing putty in your hands to soften it and make it more pliable. If the putty is too stiff, add a small amount of linseed oil and knead again.
2. Roll the putty into a rope. Roll a rope of putty about 1/2 inch thick and long enough to cover one side of the window.
3. Apply the putty to the frame. Press the putty firmly against the glass and the frame, creating a smooth, angled bead that covers the glazing points. Use a putty knife to smooth the putty and create a clean, professional-looking finish. Hold the putty knife at a slight angle and apply even pressure. Wipe the knife frequently with a clean cloth to remove excess putty.
4. Repeat for all sides. Repeat the process for all four sides of the window, ensuring that the putty forms a continuous seal around the glass. Overlap the putty slightly at the corners to prevent gaps.
5. Clean up excess putty. Use a putty knife to remove any excess putty from the glass and the frame. Wipe the glass clean with a damp cloth.

Step 6: Curing and Painting (Optional)

Allow the putty to cure completely before painting. This can take several days or even weeks, depending on the type of putty and the weather conditions. The putty is ready to paint when it forms a skin.

1. Allow the putty to cure. Place the window in a well-ventilated area and allow the putty to cure according to the manufacturer’s instructions.
2. Paint the putty. Once the putty is cured, you can paint it to match the frame. Use a high-quality exterior paint and apply two coats for best results. Painting the putty not only enhances the appearance of the window but also helps to protect it from the elements.

Step 7: Caulking (Optional)

For exterior windows, caulking around the frame can provide an extra layer of protection against the elements.

1. Apply caulk to the exterior of the frame. Using a caulk gun, apply a bead of caulk around the perimeter of the window frame where it meets the wall.
2. Smooth the caulk. Use a wet finger or a caulk smoothing tool to smooth the caulk and create a clean, watertight seal.

Choosing the Right Glass

Selecting the correct type of glass is crucial for the longevity and performance of your window repair. Here’s a breakdown of common options:

• Single-Pane Glass: This is the most basic and least expensive option. It’s suitable for older homes or windows that don’t require high energy efficiency.
• Double-Pane Glass (Insulated Glass Units – IGUs): Two panes of glass separated by a sealed air space. Provides better insulation and energy efficiency. If you’re replacing glass in a modern window, this is likely what you’ll need. The thickness of the air space and the type of gas (argon or krypton) filling it impact the insulation value.
• Tempered Glass: A type of safety glass that is much stronger than regular glass. If it breaks, it shatters into small, relatively harmless pieces instead of sharp shards. Required by code in many locations, especially for windows near doors or floors.
• Laminated Glass: Consists of two or more layers of glass bonded together with a plastic interlayer. Provides excellent security and sound insulation.
• Low-E Glass: Glass with a special coating that reflects infrared and ultraviolet light, reducing heat gain in the summer and heat loss in the winter. Improves energy efficiency.
• Obscure Glass: Textured or patterned glass that provides privacy while still allowing light to pass through.

When ordering your replacement glass, be sure to specify the type of glass, the thickness, and the exact dimensions. It’s often helpful to bring a piece of the broken glass (if possible) or a detailed diagram to the glass supplier.

Troubleshooting Common Problems

• Putty not sticking: Make sure the frame is clean and primed with linseed oil primer. The putty should also be properly kneaded and pliable. If the weather is cold, warm the putty slightly before applying it.
• Putty cracking: This is usually caused by the putty drying out too quickly. Make sure the frame is properly primed and that you’re using a high-quality putty. Avoid applying putty in direct sunlight or hot weather.
• Glass not fitting: Double-check your measurements and make sure the glass is the correct size. If the glass is slightly too large, you may be able to carefully sand down the edges. If it’s too small, you’ll need to order a new pane.
• Condensation between panes (in double-pane windows): This indicates that the seal on the insulated glass unit has failed. The entire IGU will need to be replaced; you cannot repair the seal.
• Difficulty removing old putty: Use a heat gun or hair dryer to soften the putty. Be patient and work slowly. You may also try using a special putty softener.

Maintaining Your Repaired Window

To keep your repaired window looking its best and functioning properly, follow these tips:

• Clean the glass regularly. Use a mild glass cleaner and a soft cloth to remove dirt and grime.
• Inspect the putty and caulk periodically. Look for any signs of cracks or deterioration. Repair or replace the putty or caulk as needed.
• Keep the frame painted. Paint protects the wood from the elements and helps to prevent rot and decay.
• Lubricate window hardware. Keep hinges, latches, and other hardware lubricated to ensure smooth operation.

When to Call a Professional

While replacing a broken window is often a DIY-friendly project, there are times when it’s best to call a professional:

• Large or complex windows: If you’re dealing with a large window, a window with an unusual shape, or a window that’s difficult to access, it’s best to leave the job to a professional.
• Double-pane window repair: Replacing a failed insulated glass unit (IGU) in a double-pane window requires specialized tools and knowledge.
• Window frame damage: If the window frame is significantly damaged, you may need to have it repaired or replaced by a professional carpenter.
• You’re uncomfortable with the task: If you’re not comfortable working with glass or you’re unsure about any of the steps involved, it’s always best to err on the side of caution and call a professional.

Cost Considerations

The cost of fixing a broken window can vary depending on several factors, including the size and type of glass, the complexity of the repair, and whether you hire a professional.

• DIY costs: If you do the job yourself, you’ll need to factor in the cost of the glass, putty, glazing points, primer, and any other materials you need. Expect to pay anywhere from $20 to $100 or more for the glass, depending on the type and size. Other materials will typically cost another $20 to $50.
• Professional costs: If you hire a professional, you can expect to pay $150 to $500 or more for the repair, depending on the scope of the work. This will include the cost of the glass, labor, and any other materials needed.

Conclusion

Replacing a broken window is a rewarding DIY project that can save you money and improve the appearance and energy efficiency of your home. By following these step-by-step instructions and taking the necessary safety precautions, you can successfully repair a broken window and restore your view. Remember to choose the right type of glass for your needs, prepare the frame properly, and apply the putty carefully for a long-lasting and professional-looking repair. And, if you’re ever unsure about any part of the process, don’t hesitate to call a professional.