How to Replace Window Panes

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

This is a project you could take on yourself for less than the cost of hiring an expert. It requires the right equipment and an hour or two of your time.

Glass

Replace your old single-paned windows replacement with tempered insulation glass to improve energy efficiency, cut down on noise, and preserve the original character of your old home. The replacement of windows is easy and can be accomplished by homeowners with basic hand tools. You'll also require a replacement window pane, glazier's tips, pliers, and latex glazing putty. If needed you may make use of a heat gun to warm the old putty. Wear safety glasses and gloves prior to beginning. Working with broken glass can cause serious injuries.

Take out any broken glass pieces remaining. It is recommended to use pliers however a flathead could be useful equally. Then, use a wood chisel, or putty knife, to remove the rest of the old putty from the frame and the sash. Be careful not to break the window sash. Work slowly and carefully. This is best done on an elevated ladder, not on the ground. Also, have someone lower to hold it steady.

After you have removed all the old putty, prepare the window frame to accommodate the new pane. Measure the width and height of the opening in the sash and subtract 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. Alternately, you can cut the glass yourself if you have the right tools.

After putting the new pane in place After installing the new pane, apply a small amount of caulking around the edge to make it weatherproof. Then, place a glazier's tip on each side of the frame to secure the pane in the right place. The points should not be too tight that they cause friction between the frame and sash, but they should also not be loose.

Before applying the putty on the surface, knead thoroughly until it is smooth and free from lumps. Then, roll it into pencil-size strips. The first strip should be placed in the corner of the frame, working from one corner to the other so that it is even and smooth.

Glazier's Points

The glazier's points are small triangular pieces of metal that allow glass to be secured into frames for windows without scratching or damaging the fragile surface. Learning how to use these hidden tiny helpers is simple and can save you money on professional installation or the cost of purchasing new glass.

After getting rid of the old putty glazier points as well as any remaining residue clean the frame thoroughly with an utility knife. Lightly sand the wood into the rabbet grooves if needed to smooth out rough areas. If you sand wood, protect it with painter’s tape to protect it from damage caused by accidental sanding.

Take measurements of the empty frame and record precise measurements. These measurements can be brought to an hardware or home centers store and the new pane will be cut a bit smaller. This will ensure that the pane fits comfortably and allows for expansion and contraction.

Place the new pane into the frame and press it into place firmly using your hand. Then use the point of your chisel or the back end of the putty knife to pierce the glazier's points as shown in Figure 11. The glazier's point should be aligned with the top edge of your pane, and the shoulders should be just beneath that lip.

Apply a thin layer of glazing compound on the rabbet grooves and the edges of the glass. This will protect and seal the edges. Let it dry and cure completely.

Install the new window sash once the glazing compound has dried. First, saturate the wood with a heavy coat of Linseed oil. This will stop the new putty from taking up moisture and drying out and cracking with time. Use a brush to apply this coat, or even the tip of the blade. Then, use the chisel that is on the back of the putty tool or the back of the putty handle to gently hammer the new sash or glazier's point into the rabbet grooves. Repeat this process at intervals of 10 inches around the frame.

Putty

A hurled baseball or a rock that is errant or a falling branch can cause a window pane to break or crack. Fortunately, the majority of windows can be repaired by simply putting a new piece of glass in its place. The glass is held in place by tiny metal clips known as a glazier's point and putty, which is often called glazing compound. Remove the old pane and clean the area using an abrasive, scraper that is a pull type or a wood chisel. Wear protective glasses and repaired gloves while working. You'll require a heat gun when the window is fixed into the frame.

If you're planning to install the original sash, remove any molding pieces that are used to secure the old pane. Then you can sand the sash down to ensure it's level and ready for new caulk. Once the sash is installed, you can apply a silicone caulk over the glass. This will ensure that it won't be leaking or fade over time.

Remove the glazing points from the rabbets. These are the grooves in the sash, where the glass is. If they're hard to chisel out, try holding an instrument like a heat gun over them to soften them first. When using a heated tool, make sure to not scratch the sash and its railings.

Make the bed for your new pane after you have removed the old putty and glazing points. Roll a piece of glazing compound between your hands, and repaired form it into a 1/2-inch thick. Press it into the rabbets, where the glass will be placed. It's important that the glass rests against the putty in all places on each side If you have to, lightly tap the glass into the rabbet using your thumb.

If the new pane has a crack then you can seal it with a solvent-based glass glue or silicone caulk prior to pressing it into the sash. If the crack is not sealed, you will need to apply putty to keep water out. After the putty has dried, clean the oily film off the glass using the help of a rag. Allow it to dry completely before painting. If you paint before the putty has completely dry, it won't create a strong seal and may leak or discolor in time.

Paint

If you've suffered a break in a window pane, then you may be worried about the expense of a new one. However, replacing a single glass pane doesn't need to cost a fortune when you do it yourself. In fact even windows with double panes can be replaced at only a fraction of the cost of a professional.

First, if you are working on a large window, make sure it is securely fixed to the frame. With the right tools and techniques, you can complete this task easily and quick.

If you're ready to begin with the removal of the old window by removing the glazing points made of metal that are attached to it. These are small metal triangles that function as "nails" that hold the window within the frame. They are buried beneath a bead or glazing glue that sets to form an unbreakable wedge that holds the frame firmly in position and hides the points.

After you have the old pane removed clean the surrounding frame and wood. Scrape off any old paint, and sand the rabbet grooves that the glazing points were. Sand them down to clean wood surfaces, so that you can paint the frames the same color. After sanding, apply a coat of flax oil on the wood that is not sanded down to help extend its lifespan.

Next, measure the dimensions of the window opening. It is necessary to measure the vertical and horizontal dimensions of the entire opening, as well as the thickness. Subtract 1/8 inch from each measurement to ensure you get a precise size for the new pane. This will also allow for expansion and contraction of the glass in times of seasonal change. Bring these measurements to the hardware or home improvement store and have the glass cut for you.

Now, it's time to bed the new window glass replacement 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.