How to Replace Window Panes
A cracked window pane can cause a lot of trouble. This can be an opportunity to upgrade your windows to energy efficient or insulated ones to enjoy benefits like increased comfort, increased resale value and lower utility costs.
You can do it yourself for a a fraction of what it would cost to employ an expert. It requires the right tools and an hour or two of your time.
Glass
If your single-pane windows are old broken, deteriorating or damaged, replacing them with newer glass that is tempered or insulated can improve energy efficiency and reduce noise while preserving the historic integrity of older homes. A majority of homeowners with hand tools can replace the window pane. You will also need an extra window pane, glazier's tips pliers, and latex glazing putty. If you need to you may use a heating gun to warm the old putty. Before beginning, wear gloves and safety glasses as working with broken glass can cause injuries.
Begin by removing any broken pieces of glass. It is recommended to use pliers for this however a flathead could be useful as well. Then, use a wood chisel or putty knife to remove the remaining old putty from around the frame and sash. Be careful to not scratch the replacement window handle sash. Be careful and slow. This can be done best on a ladder, not the ground. Also, have someone lower to keep it in place.
Once you have removed all of the old putty, you can prepare the window frame to fit the new pane. Take measurements of the width and height of the opening for the sash, subtracting 1/8 inch from each measurement (to allow for seasonal expansion and contraction). These measurements can be sent to a home center or hardware store to get an item cut from glass stock to the proper size. Alternatively, you can cut the glass replacement for windows yourself if have the right tools.
After installing the glass After installing the glass, apply caulking around the edge. This will make the glass weatherproof. Then, place a glazier's tip on each side of the frame to hold the pane in place. The points shouldn't be so tight as to cause friction between the frame and sash, but they also should not be too loose.
Before applying the putty on the surface, you must knead it thoroughly until it is smooth and free from lumps. Then, roll it into pencil-size strips. Apply the first strip to the frame's corner. Work from one corner to another, making sure it is even and smooth.
Glazier's Points
The glazier's points are the small triangular pieces of metal that help secure glass into frames for windows without scratching or damaging 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 as well as the glazier's point are gone and the frame is thoroughly cleaned with a knife to eliminate any remaining residue. If necessary, lightly sand the wood along the rabbet grooves to smooth out rough areas. If you decide to sand the wood, ensure you protect it with painter's tape to avoid accidental damage.
Take the dimensions of the frame and note down precise measurements. Take these measurements to a hardware store or a home center and have the new pane made slightly smaller than the frame's opening. This will ensure a secure fit and leave room for expansion and contraction.
Place the new pane in the frame and press it into place firmly with your hand. Then, you can use the point of your chisel, or the back of the putty knife to pierce the glazier's facets, as shown in Figure 11. The glazier's point should be in line with the top edge of the pane and the shoulders should be just beneath that lip.
Apply a thin layer glazing compound on the rabbet grooves and edges of new glass. This will seal and protect the edges. Allow it to dry completely and cure.
Install the new window sash after the glazing compound has dried. First, you need to coat the wood with an even layer of linseed. This will stop the new putty from drying out and cracking as it absorbs moisture. Apply the coating using a brush this coat, or the tip of the putty blade. Then use the chisel on the back of the tool or the back of the putty handle to gently hammer the new sash or glazier's tip into the rabbet grooves. Repeat this procedure every 10 inches around the frame's perimeter.
Putty
A baseball hit, a rock thrown in error or a branch falling can cause a broken or cracked window pane. Fortunately, windows can be replaced by simply putting a new piece in place. The glass is held in place with tiny metal clips known as the glazier's pointed and putty, often called glazing compound. Before installing a Replacement glass in windows pane, first take out the old one and clean up the area with an abrasive and the pull-type paint scraper or an abrasive wood chisel. Wear protective glasses and gloves while working. You'll need a heat gun in the event that the window is glued to the frame.
If you are planning to install your original sash, remove the molding that supports the old pane. Sand the sash until it's flat and ready for new caulk. After the sash has been reinstalled then, you can apply a silicone caulk over the glass. This will ensure that it won't get soiled or discolor over time.
Take out the glazing points in the rabbets. These are the grooves on the sash, which is where the glass is. If they're hard to chisel out, try holding an instrument like a heat gun to soften them first. If you're using a heating gun, make sure not to cause damage to the sash or its railings by holding the tool too closely.
Make the bed for your new pane after removing the old glaze and putty. Roll a rope made of glazing compound between your fingers, and make it around 1/2 inch thick. Then, push it into the rabbets where the glass will sit. It is essential that the glass rests against the putty in all places on both sides So if you have to tap it, gently press the glass into the rabbet using your thumb.
If the new pane is cracked, you can apply a silicone caulk or glass glue made from solvents to fill in the crack before pressing it in the sash. If not, you'll have to putty over the crack to create a tight seal and keep water out. After the putty is dry, clean the oily film off the glass using an abrasive and allow it to dry completely before painting. Paint before the putty is completely dry. It will not create a solid seal and could discolor or leak over time.
Paint
You might be worried about replacing a broken piece of glass. The truth is, replacing a single pane of glass doesn't need to be expensive even if you do it your own. In fact windows with double panes can be replaced for only a fraction of the cost of an expert.
If you are working on a large-sized window, make sure it is securely fixed to the frame. This task can be done relatively easy and fast using the proper tools and techniques.
When you are ready to start taking down the old window pane. Remove the glazing points made of metal that are attached to it. They are basically tiny metal triangles which function as "nails" that keep the window in place in the wood frame. They are submerged beneath a bead or glazing glue which hardens into an unbreakable wedge which holds the wood frame securely in place and hides the sharp edges.
After removal of the old pane clean the frame and wood. Scrape off any paint that has been used, 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 the wood, apply a layer of flax oil. This will help to prolong the life of the frame.
The next step is to measure the dimensions of the window opening. You will need to measure the vertical and horizontal dimensions of the entire opening as well as the thickness. Subtract 1/8 inch from each measurement to ensure that you get a precise size for the new pane. This will also allow for expansion and contraction of the glass in times of seasonal changes. Bring these measurements to the hardware or home improvement store and ask them to cut you 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.