How to Fix a Cracked Window and Avoid a Costly Replacement
Wild pitch? Thankfully, there's a DIY window fix.
- Safety glasses
- Cut-resistant work gloves
- Heat gun
- Utility knife or razor blade
- Cleaning cloths
- Dish soap
- Two-part epoxy
- Duct tape or painter’s tape
- Paper plate
- Wooden craft sticks
A cracked window is never a welcome surprise, but thanks to a stray baseball or hazardous objects like rogue tree branches in a windstorm, you may have to learn how to fix a cracked window eventually.
Fortunately, cracked glass repair is easy with some simple materials. If you have recently discovered a fissure in one of your home’s windows, mirrors, or other treasured glass items, consider the following step-by-step process for repairing glass.
Remove the Glass
If you need to remove the glass from its current location, it’s essential to do so carefully to avoid getting cut by broken shards. Put on safety goggles and protective gloves, then tape an "X" shape in the middle of the glass you plan to remove (use duct or blue painter’s tape). If the glass shatters as you remove it, the tape will hold all the pieces together, reducing the risk of injury.
Remove the broken pane of glass—ideally in one fell swoop—from its frame. With gloved hands, gently wiggle out any pieces that get stuck. You might have to use your heat gun to warm the putty or old glazing compound around the edges of the windowpane to loosen any final stubborn glass pieces. If need be, run the utility knife along the edge. Again, be careful.
Clean the Cracked Glass With Dish Soap
Whether you plan to move the glass or not, you’ll need to clean away dirt, debris, fingerprints, and other smudges on the glass before you begin the repairs. Use dish soap, warm water, and a cleaning cloth to wipe carefully around the cracked glass. Be sure to keep on the safety goggles and cut-resistant gloves—even light pressure can cause the crack to deepen and break.
Prepare the Epoxy
Two-part epoxy is a strong adhesive that will help you repair broken or cracked glass, but it dries quickly. You’ll need to have your workspace prepped and ready to go before you start mixing up the epoxy. Lay out cardboard sheets, and place the taped glass here—tape-side down—if you removed the glass from its original location.
Cut open the two-part epoxy containing a resin and a hardener, and pour the contents onto a clean spot of the cardboard or on a paper plate. Mix the epoxy with a wooden craft stick or toothpick for about 20 seconds or as directed on the product package.
Apply the Epoxy
It’s time to move swiftly before the epoxy hardens. Use a wooden craft stick or a putty knife, depending on the size of the crack, to apply the epoxy to the damaged area. Allow the epoxy to cure for about five minutes or per the package instructions.
Separated pieces of glass: For multiple pieces of broken glass, apply the epoxy to the broken edges of each piece, then push them together to attach.
Cracked glass: For one piece of glass, simply spread the epoxy over the cracked surface of the glass.
Cut Away Excess Epoxy
With gentle pressure, use a utility knife or razor blade to scrape excess epoxy off the surface of the glass. Keep the knife or razor blade flush with the glass and at a low angle, about 15 degrees. Move the blade away from your body to prevent accidental injuries.
Cure and Clean
Photo: Cavan Images / Cavan / Getty ImagesOnce you clear away the excess epoxy and the glass surface is smooth and even again, allow the epoxy to cure for another 24 hours. Now that the glass is dry and smooth, use a cleaning cloth and glass cleaner to clean the surface, removing any fingerprints or dust. Sweep or vacuum up any leftover glass shards. Remove any tape and place the glass panel back in its frame.
Temporary Fixes for Cracked Windows
If you don’t have time to tackle a window fix or replacement right away, you can still keep wind, water, and pests out. A temporary fix for a cracked window can also help maintain the integrity of the window and prevent the crack from spreading. Eventually, you’ll need a permanent solution, but for now, you can tackle one of these temporary fixes.
Glass Glue
A glass adhesive made for vehicle windows can work on your home’s windows, too. Buy the glass glue online or at a local automotive repair store, then apply it according to the manufacturer’s instructions.
Super Glue
Fill the cracks in the window with super glue. Wipe away excess adhesive with a clean cloth, and allow it to fully dry. Apply another layer if you still see openings in the glass.
Plastic Cover
Cut a piece of plastic, such as a plastic tarp or trash bag, to cover the size of the crack or hole. Tape the plastic cover to the window with masking tape or packing tape. If possible, place a plastic cover on both sides of the window. A plastic barrier prevents broken glass from entering your home. It also keeps out wind, rain, bugs, and animals. If you don’t have plastic, consider using cardboard, although it won’t hold up as well to moisture.
Masking or Packing Tape
Tape the crack with packing or masking tape, ideally on both sides. Extend the tape past the edges of the crack to keep it from spreading.
Nail Polish
For small cracks in your glass, you can apply clear nail polish. The adhesive properties help keep the break from expanding and seal the gap from the outdoors. Wipe away excess polish with a clean cloth. Apply up to three layers of nail polish on both sides of the window and wait for it to dry between coats.
DIY vs. Hiring a Pro
Before you begin the repair process, you should first inspect the window and evaluate whether or not the glass is worth repairing in the first place. If the glass has suffered significant damage, you should turn it over to the hands of a local window repair pro.
DIYing a glass window repair will cost up to $25 for supplies and around $200 for tools, depending on the size of your break and the quality of the materials you buy. Heat guns, the most expensive item on the tool list, range from $25 to $150, but you may not need one. The costs vary based on region, but hiring a pro to come to your home will probably run you at least $40 to $70 per hour in labor. The cost of a replacement window typically runs from $100 to $750 per window.
Paige Bennett contributed to this piece.
Frequently Asked Questions
Yes, glass sheets or cracked glass can be melted together by glass fusing. But glass fusing requires extremely high temperatures, around 1,400 degrees Fahrenheit to 1,600 degrees Fahrenheit, and a kiln to melt the glass properly. Melting glass is not a DIY project and is not a viable solution for fixing a cracked window.
You should replace your window when there is extensive damage to the panes or the window frame. While it can be worth repairing small cracks or chips in a glass window, further damage results in poor insulation and weak structural integrity. A broken window allows hot and cool air to escape your home, causing higher energy bills. Rain may also seep in, leading to costly water damage. A new window can save you from headaches, extra expenses, and security issues.
If the crack is minor, you can fix a cracked window frame with wood filler epoxy. Clean the area and protect the surrounding area with painter’s tape. Apply the wood filler and smooth the area with a putty knife. Wait for the epoxy to fully dry. You may want to sand and paint the new area to blend in with the existing frame. Consider more permanent repair through a local carpenter or window installer if the crack in your frame is larger.
