How to Replace Window Panes

A damaged or cracked window is a nuisance. This could be an opportunity to upgrade your windows to energy efficient or insulated ones to enjoy benefits such as improved comfort, increased resale value and reduced utility costs.

It's a task you can take on yourself for only a fraction of the cost of hiring an expert. It requires the right tools and only an hour or two of your time.

Glass

If your single-pane windows are outdated damaged, cracked or deteriorating replacing them with more modern glass that is tempered or insulated can increase energy efficiency and decrease noise while also preserving the original character of older homes. Most homeowners with basic hand tools can repair windows with ease. You will also require an extra window pane, glazier's suggestions, pliers, and latex glaze putty. If you need to you may use a heating gun to warm the old putty. Before starting, wear gloves and safety glasses as working with broken glass can cause injuries.

Remove any broken glass pieces remaining. This is best done using the help of pliers though using flathead screwdrivers can be effective in the pinch. Use a wood chisel, or putty knives, to take away any old putty that remains around the frame and the window sash. Take your time and work slowly making sure not to break the current window sash. It is a good idea to work on a sturdy ladder rather than on the ground, and to have someone stand below the sash to help hold it steady.

After you have removed all of the old putty, it is time to prepare the window frame for the new pane. To allow for seasonal expansion or contraction by subtracting 1/8 inch from the measurements of width and height. These measurements can be sent to an hardware or home centers store to get an item cut from stock glass to the right size. You can cut the glass yourself if you possess the appropriate tools.

After putting the new pane in place after installing the new pane, put a tiny amount of caulking along the edge to seal it against weather. Then, you can install a glazier's pointing on the frame's opposite side to secure the pane in place. The points should not be so tight as to cause friction between the frame and sash but they shouldn't be loose.

Before applying the putty knead it thoroughly until it is soft and free of lumps. Then, roll it into pencil-size strips. Place the first strip to the corner of the frame, working from one corner to the next so that it is smooth and even.

Glazier's Points

The glazier's facets are small triangular pieces of metal that allow glass to be secured into the frame of a window without damaging or scratching the delicate surface. Knowing how to use these tiny helpers is simple and can save you money on professional installation or the cost of buying new glass.

After removing the old putty, glazier points, and any other remnants clean the frame thoroughly using an utility knife. If necessary, lightly sand the wood in the grooves of the rabbet to smooth out rough areas. If you decide to sand wood, cover it with painter's tape to prevent 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 pane 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 push it in using your hands. Use the point of the chisel, or the back of the putty blade to smudge the glaziers' points as shown in Figure 11. After you're done, the points should be level with the top edge of the pane, and the raised shoulders of the points should be just below the rabbet's lip. groove.

Apply a thin layer glazing compound on the rabbet grooves and edges of the glass. This will seal and protect the edges. 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 stop the new putty drying out or cracking when it absorbs moisture. Apply the coating using a brush this coat, or the point of the blade. Then, use the chisel on the back of the putty tool or the back of the handle to gently hit the new sash, or glazier's tip into the rabbet grooves. Repeat this process at intervals of 10 inches all around the frame.

Putty

A hurled baseball or an unintentional rock, or falling branch could cause a window to break or crack. Fortunately, windows can be repaired by simply putting a new piece of glass in its the proper place. The glass is held in position by a small metal clip, referred to as a glazier's point and putty. This compound is also called glazing compound. Before installing a replacement window glass pane, first remove the old one and clean the area using the help of a rag, the pull-type paint scraper or the wood chisel. Wear gloves and safety glasses while you do this work. If the window is attached to the frame, you'll have to make use of a heat gun to soften the adhesive before taking it off.

If you are planning to replace the original sash, gently remove any molding pieces that secure the old pane. Then sand the sash to make sure it's flat and ready for a new caulk. After the sash has been reinstalled then, 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 to soften them before you do. When using a heating tool, be careful to avoid damaging the sash and its railings.

Once the old glazing points and putty have been removed make a bed for the new pane. Roll a rope made of glazing compound between your fingers, and make it around 1/2 inch thick. Press it into the rabbets where the glass will be put. The glass must rest 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 seal the crack prior to pressing it in the sash. If the crack is not sealed, you'll require putty to keep water from getting in. After the putty has dried clean the oily film off of the glass and let it dry completely before painting. If you paint before the putty has completely dry, it will not form a strong seal and may discolor or leak over time.

Paint

If you've had a broken window pane, you may be worried about the cost of a new one. In reality, replacing a single pane glass doesn't have to be costly if you do it on your own. Even a double-paned window could be replaced for a fraction of the price it will cost a professional.

If you are working with a large glass window first ensure it is securely fixed to the frame. This task is relatively easy and fast with the proper tools and techniques.

Once 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 basically small metal triangles which function as "nails" that hold the window in within the frame of wood. They are buried beneath a glaze putty or bead which hardens into solid wedge which holds the wood frame in place and hides the points.

After you have the old pane taken away Clean up the frame and wood. Scrape off any paint that has been used, and sand the rabbet grooves that the glazing points were placed. These should be sanded down to the point of being bare, so that you can paint them the same color as the rest the frame. After sanding the wood you can apply a layer flax oil. This will help to prolong the life of the frame.

Then, you need to measure the width of the window opening. You will need 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 in times of seasonal changes. 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 repaired 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.