How to Replace Window Panes

A damaged or cracked window can be a source of frustration. This could be an opportunity to upgrade to energy-efficient windows or insulated ones and enjoy advantages like improved comfort, increased resale value and reduced utility bills.

You can do it yourself for only a fraction of the cost it would cost to employ an expert. It requires the right tools and only an hour or two of your time.

Glass

Replace your old single-paned windows with tempered insulation glass to improve the efficiency of your energy, reduce noise, and protect the historical integrity of your old home. The majority of homeowners with basic hand tools can replace window pane a window pane. In addition to a new pane, the following items are needed: latex glazing putty; glazier's points; pliers; and an electric heater to warm the old putty, if needed. Wear safety glasses and gloves prior to starting. Working with broken glass could result in serious injuries.

Begin by removing any broken pieces of glass. This is best done using a pair of pliers, but a flathead screwdriver may work in the pinch. After that, use a wood chisel or putty knife to remove the remaining old putty around the frame and sash. Be careful to not break the window sash. Work slowly and carefully. This should be done on a ladder, not on the ground. Also, have someone lower to ensure it is held steady.

Once you have removed all of the old putty, prepare the window frame to accommodate the new pane. To allow for seasonal expansion or contraction, subtract 1/8 inch each from the measurements of the width and height. These measurements can be sent to a home center or hardware store to have a piece cut of stock glass to the right size. You can cut the glass yourself if you possess the right tools.

After installing the new glass Apply caulking to the edge. This will make the glass weatherproof. Then install a glazier's point on each side of the frame to hold the pane in its place. The points shouldn't be so tight as to cause friction between the sash and the frame, but they also should not be too loose.

Before applying the putty, knead it thoroughly until it's soft and free of lumps. Then make it into pencil-sized strips. Apply the first strip to the frame's corner. Work from corner to corner and ensure that it is even and smooth.

Glazier's Points

The glazier’s points are small triangular metal pieces that help secure the glass to the frame without damaging the delicate surface. Learning how to use these hidden little helpers is easy and can save you money on a professional installation or the cost of buying new glass.

After removing the old putty, glazier points, and any other leftovers clean the frame thoroughly with an utility knife. Lightly sand the wood into the rabbet grooves to smooth rough areas. If you do sand the wood, make sure to protect it by using painter's tape to prevent accidental damage.

Take the dimensions of the frame and note down precise measurements. Take these dimensions to a hardware store or home center and request that the new pane made slightly smaller than the frame's opening. This will ensure a secure fit and leave room for expansion and contraction.

Place the new pane into the frame and push it in with your hands. Then, you can use the point of your chisel or back end of the putty knife to tap in the glazier's points, as shown in Figure 11. The glazier's point should be flush against the top edge of the pane and the shoulders raised should be just below that lip.

Apply a thin layer glazing compound on the rabbet grooves as well as the edges of the new glass. This will protect and seal the edges. Allow this to dry and cure completely.

Install the new window sash when the glazing compound has dried. First, coat the wood with an even layer of linseed. This will keep the new putty from soaking up moisture and drying out and cracking with time. Apply this coat with a brush or the tip of your putty knife, then use the chisel, or the back end of the putty knife to gently hammer the new sash and glazier's point into the rabbet grooves. Repeat this process in intervals of 10 inches around the frame.

Putty

A hurled baseball or a rock that is errant or a falling branch can cause a replacement window seals to crack or break. Most windows can be replaced by simply putting in a fresh piece. The glass is held into position by a small metal clip, called a glazier’s point and putty. This compound is also called glazing compound. Before installing a new pane, first remove the old one and clean up the area with a rag and a pull-type paint scraper or an abrasive wood chisel. Wear protective glasses and gloves while doing this work. You'll need a heating gun if the window is glued to the frame.

If you plan to reinstall the original sash in the future, take care to remove the molding pieces that secure the old pane. Then you can sand the sash down to make sure it's flat and ready for a new caulk. Once the sash is re-installed then, apply a new silicone caulk around the glass to ensure it won't leak or discolor as time passes.

Take the glazing points out of the rabbets and the grooves in the sash, where the glass is. If they're difficult to work out, try holding the hand tool, such as a heat gun over them to soften them before you do. If you're using a heated gun, make sure not to scratch the railings of the sash or the sash itself by placing the tool too close.

Once the old points of glazing and putty are removed, make a bed for the new pane. Roll a rope of glazing compound between your hands, and form it to be around 1/2-inch thick. Then, push it into the rabbets in which the glass will rest. The glass must be positioned against the putty on both sides. If needed gently tap your glass into the rabbet with your thumb.

If the new pane has damaged, you can use a silicone caulk or glass glue based on solvents to cover the crack before pressing it into the sash. If not, you'll have to apply putty over the crack to create an impervious seal to keep water out. After the putty has dried clean the oily film off the glass and let it dry completely before you paint. Paint after the putty is completely dry. It won't create a solid seal and may discolor or leak over time.

Paint

You may be concerned about replacing a broken pane of glass. In reality, replace window Handle replacing a single piece of glass doesn't have to be costly if you do it on your own. In fact even windows with double panes can be replaced at less than the cost of a professional.

First, if you're working on a large-sized window, make sure it is securely fastened to the frame. Using the proper tools and techniques you can complete this task easily and speedy.

When you are ready to start with the removal of the window pane. Pry out the metal glazing points that are attached to it. These are essentially small metal triangles that function as "nails" that hold the window in in the wood frame. They are buried under a bead of glazing putty that hardens into a solid, molded wedge that holds the window firmly in place and conceals the edges.

After you have removed the old pane taken away clean the surrounding frame and wood. Scrape away any old paint and sand down the rabbet grooves, where the glazing points used to be. Sand them to bare wooden surfaces so you can paint the frames with the same color. After sanding the wood you can apply a layer flax oil. This will help to extend its life.

Then, take measurements of the dimensions of the window opening. You will need to measure the horizontal and vertical dimensions of the entire opening, as well as the thickness. To get the exact size of the new pane subtract 1/8 inch from both measurements. This will also allow for expansion and contraction of the glass in times of seasonal change. Take these dimensions to your local hardware or home improvement store and have a piece cut for you.

Now, it's time to bed the new window pane. To do this, place the pane inside the frame and move it around until a 1/16 inch of putty remains between the edge of the glass and the sash on all four sides. Use a putty knife to smear the putty evenly, making sure that there isn't an excessive amount of excess putty in the corners and along the edges. When the putty dries, it can be painted with the same color as the frame to prevent water and air from leaking into the frame and causing fogging.