How to Replace Window Panes

A cracked window pane is an inconvenience. This could be an opportunity to upgrade to energy-efficient windows or insulated ones, and reap advantages like improved comfort, increased resale values and reduced utility costs.

This is a project you could take on yourself for only a fraction of the cost of hiring an expert. It requires the right tools and an hour or two of your time.

Glass

If your single pane windows are old, deteriorating or broken, replacing them with newer glass that is tempered or insulated will increase energy efficiency and decrease noise while maintaining the historic integrity of older homes. Most homeowners with basic hand tools can repair the window pane. You'll also require an additional window pane, glazier's tips pliers, and latex glaze putty. If needed you may make use of a heat gun to warm the old putty. Before beginning, wear gloves and safety goggles as working with broken glass may cause injuries.

Begin by removing any broken pieces of glass. It is best to use pliers, but a flathead can be used as well. Make use of a wood chisel or putty knives to remove any remaining old putty around the frame and window sash. Take your time and work slowly and be careful not to damage the old window sash. It is recommended to do this on a stable ladder rather than the ground and place someone on the sash to help hold it steady.

After you've removed all the old putty, it is time to prepare the window frame for the new pane. To allow for seasonal expansion or contraction, subtract 1/8 inch each from the measurements of width and height. Take 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 right tools.

After putting in the new glass After installing the glass, apply some caulking around the edge. This will make the glass weatherproof. Install a glazier's point on both sides of the frame. This will secure the pane. The points should not be too tight that they cause friction between the frame and sash However, they should not be loose.

Before applying the putty to the surface, gently knead it until it is smooth and nearest free from lumps. Cut it into pencil-sized pieces. 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 the window frame without damaging the delicate surface. Understanding how to use these little helpers is easy and could save you money on a professional installation or the cost of new glass.

After the old putty as well as the glazier's points have been removed Clean the frame thoroughly using a utility knife to eliminate any remaining traces. If needed you can lightly sand the wood along the grooves of the rabbet to smooth out rough areas. If you sand wood protect it with painter’s tape to protect it from damage caused by accidental sanding.

Measure the empty frame's dimensions and record precise measurements. These dimensions can be taken to an hardware or home centers store and the new pane will be cut to a smaller size. This will ensure a tight fit and will allow room for expansion and contraction.

Insert the new pane into the frame and press it down using your hands. Then use the point of your chisel, or the back of the putty knife to pierce 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 shoulders raised should be just beneath that lip.

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

Install the new window sash once the glazing compound has dried. The first step is to coat the wood with an even layer of linseed. This will prevent the new putty from soaking in the moisture and deteriorating and cracking with time. Apply the coating using a brush this coat, 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 handle to gently hit the new sash, or glazier's point into rabbet grooves. Repeat this procedure every 10 inches along the perimeter of the frame.

Putty

A baseball hit or a rock thrown in error, or a tree falling could result in a broken or cracked window pane. The majority of windows can be repaired easily by installing a new piece. The glass is held in the position with a tiny metal clip, called a glazier's point and putty. This compound is also known as glazing compound. Before you install a new pane, first take out the old one and clean the area with a rag and an abrasive scraper that is a pull type or a wood chisel. Wear gloves and safety glasses when working. You'll require a heat gun in the event that the window is glued into the frame.

If you are planning to reinstall your original sash, you must remove the mold that holds the old pane. Then sand the sash window replacement to ensure it's level and ready for a new caulk. Once the sash is re-installed then, apply a new caulk made of silicone around the glass to ensure that it won't leak or discolor over time.

Take the glazing points out of the rabbets, or the grooves in the sash that the glass sits. If they're hard to chisel, hold a hand tool like a heat gun over them for a few minutes to soften them. When using a heated tool, make sure to avoid damaging the sash's railings and sash.

After the old points of glazing and putty have been removed prepare a bed for the new pane. Roll a rope of glazing compound between your hands, and form it into a 1/2-inch thick. Then, you can press it into the rabbets in which the glass will rest. The glass must be positioned against the putty on both sides. If you need to you want to tap your glass lightly into the rabbet using your thumb.

If the new pane is cracked, you can cover it with a solvent-based glass glue or silicone caulk prior pressing it into the sash. In other cases, you'll need to apply putty over the crack to create a tight seal and keep water out. After the putty has dried remove the oily film off the glass and allow it to dry completely before you paint. If you paint before the putty has completely dry, it will not form a solid seal and could be leaking or discoloring over time.

Paint

If you've experienced a broken window pane, then you may be worried about the expense of replacing it. In reality, replacing a single pane glass doesn't have to be expensive even if you do it your own. In fact even windows with double panes can be replaced at a fraction of the cost of a professional.

If you are working on a large-sized window replacement companies, ensure that it is securely attached to the frame. With the right tools and techniques, you can complete this task easily and quick.

If you're ready to begin with the removal of the old window by prying out the glazing points of metal that are connected to it. They are basically tiny metal triangles that act as "nails" which hold the window in place in the wood frame. They are placed under a glaze putty or bead that hardens to an unbreakable wedge which holds the wood frame in place and hides the sharp edges.

After you have the old pane removed clean the surrounding frame and wood. Scrape off any old paint and sand the rabbet grooves where the glazing points were. Sand them down to bare wood surfaces, so that you can paint the frames 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 determine the vertical and horizontal dimensions of the entire opening as well as the thickness. Subtract 1/8 inch from each measurement to ensure you get a precise size for the new pane. This will also allow for expansion and contraction of the glass in times of seasonal change. You can take these measurements to a hardware store or home improvement shop and have 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.