How to Replace Window Panes

A cracked window pane is a nuisance. This can be an opportunity to upgrade to energy-efficient windows or insulated ones, and reap advantages like improved comfort, increased resale values and lower utility costs.

You can do it yourself at less than what it would cost to hire an expert. It requires the right equipment and an hour or two of your time.

Glass

If your single-pane windows are outdated damaged, cracked or deteriorating replacing them with modern glass that is tempered or insulated will increase energy efficiency and decrease noise while preserving the original character of older homes. A majority of homeowners with hand tools can replace the window pane. You will also require an extra window pane, glazier's suggestions, pliers, and latex glazing putty. If necessary you can use a heating gun to warm the old putty. Wear safety glasses and gloves prior to starting. Working with broken glass could result in serious injuries.

Take away any broken glass pieces remaining. It is best to use pliers however a flathead could work equally. Use a wood chisel, or putty knives to remove any old putty remaining around the frame and window sash. Be careful not to scratch the window sash. Take your time and work slowly. This is best done on a ladder, not on the ground. Also, you should have someone on the ground to keep it in place.

After you have removed all the old putty, it is time to prepare the window frame to fit the new pane. Find the width and the height of the opening in the sash, subtracting 1/8 inch from each measurement (to allow for seasonal expansion and contraction). Take these measurements to a hardware store or home center, and find a piece glass cut to size. Alternatively, you can cut the glass yourself if have the right tools.

After installing the new glass After installing the glass, apply caulking to the edge. This will make the glass weatherproof. Install a glazier's point on both sides of the frame. This will secure the pane. The points shouldn't be too tight that they create friction between the sash and frame, but they also shouldn't be too loose.

Before applying the putty to the surface, you must knead it thoroughly until it becomes soft and free from lumps. Cut it into pencil-sized pieces. Apply the first strip to the corner of the frame. Work from one corner to the next, making sure it is even and replace window pane smooth.

Glazier's Points

The glazier's points are tiny triangular pieces of metal that allow glass to be secured into the window frame without damaging the delicate surface. Learning how to use these little helpers is easy and could save you money on a professional installation or the cost of purchasing new glass.

After removing the old putty, glazier points and any residue, clean the frame thoroughly with an utility knife. If needed you can lightly sand the wood in the rabbet grooves to smooth rough spots. If you do sand the wood, be sure to protect it by using painter's tape to prevent accidental damage.

Measure the empty frame's dimensions and note down precise measurements. These dimensions can be taken to a home center or hardware store and the new pane will be cut slightly smaller. This will ensure a tight fit and will allow room for expansion and contraction.

Place the new pane into the frame and press it in place using your hand. Use the chisel's point or the back of the putty knife to smudge the glazier's points, as illustrated in Figure 11. The glazier's points should sit aligned with the top edge of the pane and the shoulders should be just below the lip.

Apply a thin bead of glazing compound on the edges of the new glass and in the rabbet grooves, to seal and protect them. Let it dry completely and cure.

Install the new window sash after the glazing compound has dried. First, saturate the wood with a heavy coat of Linseed oil. This will prevent the new putty drying out or cracking as it absorbs moisture. Apply the coating using a brush this coat, or the point of the putty blade. Then use the chisel on the back of the putty tool or the back of the handle to gently hammer the new sash or glazier's point into rabbet grooves. Repeat this process at intervals of 10 inches all around the frame.

Putty

A baseball thrown or a rock thrown in error, or a fallen tree can result in a cracked or cracked window. Luckily, most windows can be replaced by simply placing a new piece in the right place. The glass is held in the position with a tiny metal clip, also known as the glazier's point, and putty. This compound is also referred to as glazing compound. Before installing a replacement sash windows pane, first get rid of the old one and clean up the area using the help of a rag, the pull-type paint scraper or an abrasive wood chisel. Wear safety glasses and gloves while working. If the window is glued to the frame, you'll need to use a heat gun to soften the adhesive prior to cutting it loose.

If you are planning to replace window pane (Additional Info) the original sash, replace Window Pane remove any pieces of molding that are used to secure the old pane. Then, sand the sash to ensure it's smooth and ready for new caulk. Once the sash is installed, you can apply a silicone caulk to the glass. This will ensure that it won't get soiled or discolor over time.

Remove the glazing points from the rabbets. These are the grooves on the sash where the glass is. If they're difficult to cut out, try holding the hand tool, such as a heat gun over them to soften them first. When using a heated tool, be sure to not damage the sash's railings and sash.

Create the bed for your new pane after removing the old glaze points and putty. Roll a rope with glazing compound between your fingers and make it around 1/2 inch thick. Then, you can press it into the rabbets in which the glass will sit. It is crucial that the glass rests against the putty in all places on both sides If you have to tap it, gently press the glass into the rabbet with your thumb.

If the new pane is cracked, you can cover it with a solvent-based glass glue or silicone caulk prior pressing it into the sash. If the crack is not sealed, you will need to use putty to keep the 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 form a good seal and may discolor or leak over time.

Paint

If you've experienced a broken window pane, then you may be concerned about the expense of replacing it. In reality, replacing a single pane of glass doesn't need to be expensive when you do it on your own. Even a double glazing replacement window-paned window could be replaced for a fraction of what it costs a professional.

If you are working with a large glass window, first make sure it is securely fixed to the frame. Using the proper tools and techniques, you can make this task relatively easy and fast.

When you are ready to begin, remove the old window pane. Take out the metal glazing points attached to it. These are small metal triangles that act as "nails" that hold the window within the frame. They are submerged beneath a layer of glazing putty, which is then cured to form a solid, molded wedge which holds the window in place and hides the edges.

After you have the old pane taken away Clean up the frame and wood. Scrape off any paint and sand down the rabbet grooves where the glazing points used to be. These should be sanded down to bare wood to allow you to paint them the same shade as the rest of the frame. 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 take horizontal and vertical measurements of the entire opening as well as the thickness of the old pane. To get the exact size of the new pane subtract 1/8 inch from both measurements. This will allow for seasonal changes in the glass. Bring these measurements to the 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.