How to Replace Window Panes

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

It's a task you can take on yourself for a fraction of the cost of hiring a professional. You'll need only the proper tools and a few hours of your time.

Glass

Replace window pane your single-paned windows with tempered insulation glass to improve energy efficiency, cut down on noise, and maintain the historic integrity of your old home. The replacement of a window pane is relatively simple and can be done by homeowners with basic hand tools. Alongside a replacement pane, the following items are needed such as latex glazing putty; glazier's points; pliers; and a heat gun for warming the old putty, if needed. Before starting, put on protective gloves and goggles since working with broken glass can cause injuries.

Begin by removing any remaining broken pieces of glass. This is best done using the help of pliers though using a flathead screwdriver can also work in a pinch. Utilize a wood chisel or putty knives to remove any old putty remaining around the frame and window sash. Be careful not to damage the window sash. Take your time and work slowly. It is best to do this on a sturdy ladder rather than the ground and to have someone standing below the sash to help keep it steady.

Once you've removed all the old putty, you can prepare the window frame to fit the new pane. Measure the width and height of the opening in the sash, 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 get a piece of stock glass cut to size. Alternately, you can cut the glass yourself, if you have the appropriate tools.

After installing the new glass, apply caulking around the edge. This will make the glass weatherproof. Then, you can install a glazier's pointing on each side of the frame to secure the pane in the right place. The points shouldn't be so tight that they cause friction between the frame and the sash however they should not be loose.

Before applying the putty make sure to knead it until it's soft and free of lumps. Roll it into pencil-sized strips. Apply the first strip to the corner of the frame, working from one corner to the other 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 frames for windows without damaging or scratching the delicate surface. It's easy to learn how to use this hidden tool and you can save money on the expense of a professional installation.

After the old putty and the glazier's point are gone and the frame is thoroughly cleaned using a utility knife to get rid of any remaining traces. Lightly sand the wood into the rabbet grooves if needed to smooth rough areas. If you do sand the wood, make sure to protect it by using painter's tape to prevent accidental damage.

Measure the empty frame's dimensions and write down accurate measurements. Take these dimensions to a hardware store or home center and request that the new pane cut slightly smaller than the frame's opening. This will ensure that the pane fits perfectly and allows for expansion and contraction.

Place the new pane into the frame and press it down using your hands. Use the point of the chisel, or Replace window pane the back of the putty blade to tap in the glazier's points as illustrated in Figure 11. When you're done, they should be flush with the top edge of the pane. the shoulders of the points should be below the rabbet's rim groove.

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

After the glazing compound dries, you're ready to install the new window sash. First, coat the wood with a heavy coat of linseed oil. This will prevent the new putty from taking in the moisture and drying out and cracking over time. Apply the coating using a brush 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 hit the new sash, or glazier's tip into the rabbet grooves. Repeat this process at intervals of 10 inches around the frame.

Putty

A baseball hit, a rock thrown in error, or a tree falling can cause a broken or cracked window pane. Most windows can be repaired easily by installing a new piece. 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 installing a new pane, first take out the old one and clean up the area using an abrasive and a pull-type paint scraper or a wood chisel. Wear protective glasses and gloves while working. If the window is secured to the frame, you'll need to use a heat gun to soften the adhesive before taking it off.

If you are planning to replace the original sash in the future, take care to remove any pieces of molding that hold the old pane in place. Then sand the sash to make sure it's flat and ready to be re-caulked. 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, which is where the glass is located. If they're hard to chisel out, you can try holding a hand tool like a heat gun to soften them before you do. When using a heat tool, be sure to avoid damaging the sash or its railings.

Prepare a bed for your new pane after you have removed the old glaze and putty. Roll a piece of glazing compound between your hands, and form it to be 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 you want to tap your glass lightly into the rabbet with your thumb.

If the new pane has cracked, you can apply a silicone caulk or glass glue based on solvents to fill in the crack before pressing it in the sash. If the crack is not sealed, you'll require putty to keep the water out. After the putty has dried, wipe the oily film from the glass and allow it to dry completely before painting. If you paint before the putty has completely dry, it won't create an effective seal and could be leaking or discoloring over time.

Paint

You might be worried about replacing a broken piece of glass. But the truth is that replacing one glass pane does not have to break the bank when you do it yourself. Even double glazing window replacement-paned windows can be replaced at a fraction of the cost it costs for a professional.

First, if you are working on a large window, make sure it is securely fastened to the frame. This task is relatively easy and quick with the right tools and techniques.

Once you're ready to begin, begin by removing the old window by prying out the glazing points made of metal that are attached to it. These are tiny triangles of metal which act as "nails", holding the window in the frame. They are buried under a bead of glazing putty, which hardens into a solid, moulded wedge which holds the window in place and conceals the points.

Once you have the old pane taken away Clean up the frame and wood. Scrape off any paint and sand down the rabbet grooves where the glazing points were. Sand them down to bare wooden surfaces, allowing you to paint the frames with the same color. After sanding, apply a coat of flax oil on the wood that is not sanded down to extend the life of the frame.

The next step is to measure the dimensions 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 get the exact size 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 a hardware or home improvement store and ask them to cut you cut the glass 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.