How to Replace Window Panes

A damaged or cracked window can be a source of frustration. It could also be an opportunity to upgrade your glass to energy efficient or insulated windows replacement to benefit from greater comfort, a higher resale value and reduced utility bills.

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

Glass

Replace your single-paned windows with tempered or insulation glass to improve energy efficiency, reduce noise, and maintain the historical integrity of your old home. The procedure of replacing windows is simple and can be done by homeowners with basic hand tools. In addition to a replacement pane, the following items are required for the replacement process: latex glazing putty pliers, glazier's points and an electric heater to warm the old putty, if necessary. Before beginning, wear gloves and safety goggles as working with broken glass could cause injuries.

Take away any broken glass pieces remaining. This can be done with pliers, though using a flathead screwdriver may be used in the pinch. Then, use a wooden chisel or putty knife remove the rest of the old putty from around the frame and the sash. Take your time and work slowly, taking care not to break the existing window sash. This should be done on an elevated ladder, not on the ground. Also, you should have someone lower to keep it in place.

After you've removed all the old putty, it is time to prepare the window frame to fit the new pane. Take measurements of the width and height of the sash opening by subtracting 1/8 inch from each measurement (to allow for seasonal expansion and contraction). Bring 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 right tools.

After putting the new pane in place 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 each side of the frame to hold the pane in place. The points shouldn't be so tight that they cause friction between the frame and sash but they shouldn't be loose.

Before applying the putty on the surface, you must knead it thoroughly until it becomes soft and free of lumps. Then, roll it into pencil-size strips. Apply the first strip to the frame's corner. Work from corner to corner, making sure it is even and 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. Understanding how to use these hidden tiny helpers is simple and could save you money on professional installation or the cost of new glass.

Once the old putty and glazier's points are removed, thoroughly clean the frame with a knife to eliminate any remaining traces. If needed it is necessary to lightly sand the wood along the grooves of the rabbet to smooth out rough spots. If you decide to sand the wood, make sure to protect it with painter's tack to avoid accidental damage.

Take measurements of the empty frame and record precise measurements. Take these measurements to an hardware store or home center, and have the new pane cut smaller than the frame's opening. This will ensure a snug fit and will allow room for expansion and contraction.

Place the new pane into the frame and press it into the frame using your hand. Then, you can use the point of your chisel or the back of the putty knife to make a tap on the glazier's points, as shown in Figure 11. The glazier's points should be in line with the top edge of your pane and the shoulders raised should be just beneath that lip.

Apply a small amount of glazing compound on the edges of the new glass and in the rabbet grooves to seal and nearest protect them. Allow it to dry and cure completely.

Install the new window sash once the glazing compound has dried. First, coat the wood with an even layer of linseed. This will prevent the new putty from drying out or cracking when it absorbs moisture. Use a brush to apply this coat, or the point of the putty blade. Then use the chisel on the back of the 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 procedure every 10 inches around the perimeter of the frame.

Putty

A baseball hit or a rock thrown by error, or a fallen tree can cause a broken or cracked window. Fortunately, the majority of windows can be easily replaced by simply putting a brand new piece in the proper place. The glass is held in place with a small metal clip called a glazier's point, and putty, which is often called glazing compound. Before you install a new pane, first take out the old one and clean the area using an abrasive and the pull-type paint scraper or the wood chisel. Wear safety glasses and gloves while doing this work. If the window is secured to the frame, you'll have to make use of a heat gun to soften the adhesive prior to prying it free.

If you are planning to replace the original sash in the future, take care to remove any molding pieces that secure the old pane. Then, sand the sash to make sure it's flat and ready for new caulk. Once the sash is reinstalled then, you can apply a silicone caulk on the glass. This will ensure that it won't be leaking or fade over time.

Remove the glazing points from the rabbets, or the grooves in the sash where the glass is. If they're difficult to cut, place an instrument like a heat gun over them to soften first. If you're using a heating gun, be cautious not to scratch the railings or sash by placing the tool too tightly.

After the old glazing points and putty have been removed, prepare a bed for the new pane. Roll a rope of glazing compound between your hands, forming it to be around 1/2-inch thick. Then, you can press it into the rabbets where the glass will be. It's important that the glass sits on the putty in all places on each side If you have to tap it, gently press the glass into the rabbet with your thumb.

If the new pane is damaged, you can use the silicone caulk or glass glue made from solvents to fill in the crack before pressing it into the sash. If not, you'll have to apply putty on the crack to form an impervious seal to keep water out. After the putty has dried and the film is oily, wipe it off the glass with a rag and allow it to completely dry before painting. Paint before the putty has completely dried. It won't form a good seal and may leak or discolor with time.

Paint

If you've had a broken window pane, then you may be worried about the cost of a new one. The truth is, replacing a single piece of glass doesn't have to be costly even if you do it your own. Even a double-paned window can be replaced for a fraction of what it will cost a professional.

If you're working with large glass windows first, ensure that it is securely attached to the frame. This can be made relatively simple and fast using the proper tools and techniques.

If you're ready to begin, begin by removing the old window replacement companies pane by removing the metal glazing points that are attached to it. These are tiny triangles of metal which act as "nails" that hold the window in place. They are buried beneath a glaze putty or bead which hardens into an unbreakable wedge which holds the wood frame firmly in position and hides the points.

After removing the old pane, clean the frame and wood. Scrape away any old paint and sand down the rabbet grooves where the glazing points used to be. Sand them down to bare wooden surfaces, allowing you to paint the frames with the same shade. After sanding the wood you can apply a layer flax oil. This will help to prolong the life of the frame.

Next, measure the size of the window opening. It is necessary to take horizontal and vertical measurements of the entire opening as well as the thickness of the old pane. To determine the exact dimensions of the new pane, subtract 1/8 inch from both measurements. This will allow for seasonal changes in the glass. Take these measurements to the hardware or home improvement store, and they will 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.