How to Replace Window Panes

A damaged or cracked window is a nuisance. It can also be a chance to upgrade your glass to energy efficient or insulated windows to reap benefits like greater comfort, a higher potential for resales, and less costs.

It's a task you can do yourself for a fraction of 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 with tempered insulate glass to improve energy efficiency, cut down on noise, and maintain the original character of your older home. Most homeowners with basic hand tools can repair a window pane. You will also need an extra window pane, glazier's tips pliers, and latex glaze putty. If necessary you can use a heating gun to warm the old putty. Wear safety goggles and gloves prior to starting. Working with broken glass could result in serious injuries.

Take away any broken glass pieces that remain. It is best to use pliers however a flathead could be used equally. Then, use a wooden chisel or putty knife take the remainder of the old putty from around the frame and the sash. Work slowly and carefully, taking care not to break the existing window sash. It is best to do this on a sturdy ladder rather than on the ground and to have someone standing below the sash to help keep it steady.

Make sure the window frame is ready to receive the new pane once you have removed the old putty. Find the width and the height of the opening for the sash, subtracting 1/8 inch from each measurement (to allow for seasonal expansion and contraction). Take these measurements to the nearest hardware store or home center and have a piece of stock glass cut to size. You can cut the glass yourself if you have the appropriate tools.

After installing the new pane After installing the new pane, apply a small amount of caulking around the edges to seal it against weather. Then install a glazier's point on the frame's opposite side to secure the pane into place. The points should not be so tight that they cause friction between the sash and frame however they shouldn't be too loose.

Before applying the putty, work it in a gentle manner until it is smooth and free of lumps. Roll it into pencil-sized strips. Apply the first strip to the corner of the frame. Work from one corner to the next and ensure that it is even and smooth.

Glazier's Points

The glazier's points are tiny triangular metal pieces that allow glass to be secured to the frame without causing any damage to the fragile surface. Knowing how to use these tiny pieces of help is simple and can save you money on a professional installation or the cost of new glass.

After getting rid of the old putty glazier points and any leftovers, clean the frame thoroughly using a utility knife. Lightly sand the wood into the rabbet grooves, if necessary, to smooth rough areas. If you decide to sand wood, protect it with painter’s tape to avoid accidental damage.

Write down the exact dimensions of the frame. These measurements can be brought to an hardware or home centers store, and the new frame will be cut a bit smaller. This will ensure a secure fit and leave room for expansion and contraction.

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

Apply a thin bead of glazing compound on the edges of the new glass and into the rabbet grooves to seal and protect them. Allow it to dry and cure fully.

Install the new window replacements sash when the glazing compound has dried. First, you need to coat the wood with an even layer of linseed. This will keep the new putty from taking up the moisture and drying out and cracking over time. Use a brush to apply this coat, or the point 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 smash the new sash or glazier's tip into the grooves of the rabbet. Repeat this process every 10 inches around the frame's perimeter.

Putty

A baseball thrown or a rock thrown in error, or a tree falling can result in a cracked or cracked window pane. Fortunately, the majority of windows can be easily replaced by simply placing a new piece in the proper place. The glass is held into place by a small metal clip, called a glazier's point and putty. This compound is also known as glazing compound. Before you install a new pane, first remove the old one and clean the area with an abrasive and a pull-type paint scraper or an abrasive wood chisel. Wear protective glasses and gloves when working. If the window is secured to the frame, you'll have to employ a heat gun in order to soften the adhesive prior to taking it off.

If you are planning to replace the original sash, remove any pieces of molding that hold the old pane in place. Then you can sand the sash down to ensure it's smooth and ready for new caulk. Once the sash is put back in place then, you can apply a silicone caulk over the glass. This will ensure that it doesn't leak over time or discolor.

Take out the glazing points in the rabbets. These are the grooves on the sash where the glass is. If they're difficult to work out, you can try holding the hand tool, such as a heat gun to soften them up first. If you're using a heat gun, be careful not to scratch the sash or its railings by placing the tool too closely.

Make a bed for your new pane after removing the old glaze and putty. Roll a rope of glazing compound between your fingers and make it about 1/2 inch thick. Place it into the rabbets, where the glass will be put. It is essential that the glass sits on the putty in all places on each side, so if you need to tap it, gently press the glass into the rabbet using your thumb.

If the new pane is cracked, you can use the silicone caulk or glass glue based on solvents to fill in the crack prior to pressing it into the sash. If the crack is not sealed, you will need to apply putty to keep water from getting in. When the putty dries then clean the oily film off the glass with the help of a rag. Allow it to dry completely prior to painting. If you paint before the putty has completely dry, it won't form a strong seal and may leak or discolor in time.

Paint

If you've had a broken window pane, then you may be concerned about the expense of a new one. However, replacing a single glass pane doesn't need to cost a fortune if you do it yourself. In fact windows with double panes can be replaced for less than the cost of a professional.

If you are working on a large-sized window, ensure that it is securely fixed to the frame. With the right tools and techniques to accomplish this task fairly easily and fast.

When you are ready to begin with the removal of the window pane. Pry out the metal glazing points that are attached to it. These are small metal triangles which act as "nails", holding the window in the frame. They are submerged beneath a bead or glazing putty that hardens to an unbreakable wedge that holds the frame securely in place and hides the sharp edges.

After you have removed the old pane taken away Clean up the frame and wood. Scrape away any paint and sand down the rabbet grooves where the glazing points were. 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 then apply a layer of flax oil. This will help to extend its life.

The next step is to determine the size of the window's opening. It is necessary to take vertical and horizontal measurements of the entire opening and also the thickness of the old pane. To determine the exact dimensions of the new pane, subtract 1/8 inch from both measurements. This will also allow for expansion and contraction of the glass during seasons of change. Take these measurements to the hardware or home improvement store and ask them to cut you 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 nearest 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.