How to Replace Window Panes

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

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

Glass

Replace Window Pane your single-paned windows with tempered or insulated glass to increase energy efficiency, reduce noise, and maintain the original character of your old home. Most homeowners with basic hand tools can repair a window pane. In addition to a replacement sash windows pane, the following components are required: latex glazing putty; Glazier's points; pliers and an electric heater to warm the old putty if required. Wear safety glasses and gloves prior to starting. Working with broken glass can cause serious injuries.

Begin by removing any broken pieces of glass. It is best to use pliers, but a flathead can work as well. After that, use a wood chisel or putty knife to remove the remaining old putty from the frame and the sash. Be careful to not scratch the window sash. Take your time and work slowly. It is a good idea to work on a sturdy ladder rather than on the ground, and to have someone standing below the sash to help keep it steady.

Once you have removed all of the old putty, it is time to prepare the window frame to accommodate the new pane. Measure the width and height of the opening for 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. You can cut the glass yourself if you possess the right tools.

After installing the new pane, run a small bead of caulking around the edge to ensure it is weatherproof. Then, you can install a glazier's pointing on each side of the frame to hold the pane in its place. The points should not be so tight as to cause friction between the sash and frame, but they also should not be too loose.

Before applying the putty, work it in a gentle manner until it's soft and free of lumps. Roll it into pencil-sized strips. The first strip should be glued to the corner of the frame. Work from one corner to the next, making sure 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 delicate surface. It's easy to understand how to use this hidden tool, and you'll save money on the cost of an expert installation.

After removing the old putty, glazier points, and any other remnants Clean the frame thoroughly using an utility knife. Lightly sand the frame in the rabbet grooves to smooth rough areas. If you decide to sand the wood, ensure you protect it with painter's tack to avoid accidental damage.

Write down the exact dimensions of the frame. These measurements can be taken to an hardware or home centers store and the new pane will be cut slightly smaller. This will ensure that the pane fits comfortably and allows for expansion and contraction.

Place the new pane in the frame and push it in place using your hand. Use the chisel's point, or the back of the putty knife to tap in the glazier's points, as shown in Figure 11. When you're done, they should be level with the top edge of the pane and the shoulders that are raised of the points should be just below the rabbet's rim groove.

Apply a small amount of glazing compound over the edges of the new glass and into the rabbet grooves to seal and protect them. Let it dry completely and cure.

Install the new window sash when the glazing compound has dried. First, coat the wood with a thick coat of linseed oil. This will stop the new putty from drying out and cracking as it absorbs moisture. Apply the coating using a brush this coat, replace window Pane 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 in intervals of 10 inches around the frame.

Putty

A baseball that is thrown, an errant rock or a fallen branch can cause a window pane to crack or break. Luckily, most windows can be easily replaced by simply putting a new piece of glass in its place. The glass is held in place with tiny metal clips known as a glazier's point, and putty, also called glazing compound. Remove the old pane and clean the area using the rag, a pull-type scraper, or a wood chisel. Wear safety glasses and gloves while doing this work. You'll need a heat gun in the event that the window is glued into the frame.

If you're planning to install the original sash in the future, take care to remove the molding pieces that hold the old pane in place. Then you can sand the sash down to ensure it's level and ready for new caulk. Once the sash is re-installed and sanded, apply a fresh caulk made of silicone around the glass to ensure that it doesn't swell or fade as time passes.

Remove the glazing points in the rabbets. These are the grooves on the sash, which is where the glass is. If they are hard to cut, place the hand tool, such as a heatgun over them for a few minutes to soften them. When using a heating tool, make sure to avoid damaging the sash's railings and sash.

Once the old glazing points and putty are removed, prepare a bed for the new pane. Roll a rope of glazing compound between your fingers, and then make it about 1/2 inch thick. Then, push it into the rabbets in which the glass will rest. The glass should rest against the putty on both sides. If necessary you want to tap your glass lightly into the rabbet using your thumb.

If the new pane has cracked, you can use a silicone caulk or glass glue that is based on solvents to fill in the crack before pressing it in the sash. If not, you'll have to apply putty over the crack to form an airtight seal and keep water out. After the putty is dry, clean the oily film off the glass using the help of a rag. Allow it to completely dry before painting. If you paint before the putty is fully dry, it won't create a strong seal and may discolor or leak over time.

Paint

You may be concerned about replacing a damaged piece of glass. But the truth is that replacing one glass pane does not need to cost a fortune If you can do it yourself. Even double glazed windows replacement-paned windows can be replaced at a fraction of the cost it would cost for a professional.

If you are working on a large window, make sure it is securely attached to the frame. With the right tools and techniques you can make this task relatively easy and speedy.

When you are ready to begin, remove the old window pane. Remove the metal glazing points attached to it. They are basically tiny metal triangles which function as "nails" which hold the window in in the wood frame. They are submerged beneath a layer of glazing putty that is then cured to form a solid, moulded wedge that secures the window in place and conceals the window's points.

After you have the old pane removed, clean up the surrounding frame and wood. Scrape away any old paint and sand down the rabbet grooves, where the glazing points were. These should be sanded to bare wood to allow you to paint them the same color as the rest the frame. After the sanding process, apply a coat of flax oil to the bare wood to prolong its life.

Next, measure the size of the window opening. You'll need to take horizontal and vertical measurements of the entire opening as well as the thickness of the old pane. To determine the exact size of the new pane subtract 1/8 inch from both measurements. This will allow for seasonal changes in the glass. You can take these measurements to a hardware or home improvement shop and get the glass 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.