How to
replace window pane Window Panes
A damaged or cracked window can be a source of frustration. It could be a chance to upgrade your windows to energy efficient or insulated ones to enjoy benefits such as improved comfort, increased resale value and reduced utility bills.
You can do it yourself for a only a fraction of the cost it would cost to hire an expert. It requires the right equipment and an hour or two of your time.
Glass
Replace your old single-paned windows using tempered or insulate glass to improve energy efficiency, cut down on noise, and protect the historical integrity of your old home. The procedure of replacing a window pane is relatively simple and can be done by homeowners with basic hand tools. In addition to a replacement pane, the following tools are required: latex glazing putty; glazier's points; pliers; and an electric heater to warm the old putty, if needed. Wear safety goggles and gloves prior to beginning. Working with broken glass could result in serious injuries.
Take away any broken glass pieces that remain. This is best accomplished with the help of pliers but a flathead screwdriver may work in a pinch. Utilize a wood chisel or putty knives, to take away any remaining old putty around the frame and the window sash. Be careful not to scratch the window sash. Work slowly and carefully. It is a good idea to do this using a sturdy ladder instead of the ground and to have someone standing below the sash in order to help hold it steady.
After you have removed all the old putty, you can prepare the window frame for the new pane. To allow for seasonal expansion or contraction and contraction, subtract 1/8 inch from the measurements of the width and height. Take these measurements to an 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 glass Apply a small amount of caulking on the edges. 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 so tight that they create friction between the sash and frame however they should not be too loose.
Before applying the putty to the surface, knead thoroughly until it is soft and free from lumps. Then, roll it into pencil-size strips. Apply the first strip in the corner of the frame, moving from one corner to another to ensure it is even and smooth.
Glazier's Points
The glazier's facets are small triangular pieces which help to secure glass into a window frame without scratching or damaging the delicate surface. Knowing how to use these hidden 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 remnants, clean the frame thoroughly using a utility knife. If needed it is necessary to lightly sand the wood in the rabbet grooves to smooth out rough areas. If you do sand the wood, be sure to protect it by using painter's tape to prevent accidental damage.
Take measurements of the empty frame and record precise measurements. Bring these measurements to a hardware store or a home center, and have the new pane cut slightly smaller than the frame's opening. This will ensure a secure fit and will allow room for expansion and contraction.
Place the new window in the frame and press it into the frame using your hand. Use the point of the chisel, or the back of the putty knife to tap in the glazier's points as shown in Figure 11. After you're done, the points should be in line with the top edge of the pane and the shoulders of the points should be just below the lip of the rabbet groove.
Apply a thin layer of glazing compound to the rabbet grooves and the edges of the glass. This will seal and protect the edges. Let it dry and cure completely.
Install the new
window glass replacement sash after the glazing compound has dried. The first step is to coat the wood with an even layer of linseed. This will keep the new putty from sucking up the moisture and deteriorating and cracking with time. Apply the coating using a brush this coat, or even the tip of the putty blade. Then use the chisel 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 grooves of the rabbet. Repeat this procedure every 10 inches along the frame's perimeter.
Putty
A hurled baseball, an errant rock or falling branch could cause a window pane to break or crack. Fortunately, windows can be repaired by simply placing a new piece in the proper place. The glass is held in place with small clips made of metal called a glazier's point, and putty, also called glazing compound. Remove the old pane and clean the area using the rag, a scraper that is a pull type or a wood chisel. Wear gloves and safety glasses 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 reinstall the original sash, take off the molding that supports the old pane. Sand the sash until it is flat and ready to receive new caulk. Once the sash is re-installed and sanded, apply a fresh silicone caulk to the glass to ensure that it will not leak or change color as time passes.
Remove the glazing points from the rabbets. These are the grooves on the sash where the glass is located. If they're difficult to cut out, try holding an instrument like a heat gun to soften them first. When using a heated tool, be careful to not scratch the sash and its railings.
Once the old glaze points and putty are removed, prepare a bed for the new pane. Roll a rope of glazing compound between your fingers,
replace window pane and make it around 1/2 inch thick. Then, push it into the rabbets where the glass will rest. It's important that the glass sits on the putty on each side, so if you need to, lightly tap the glass into the rabbet using your thumb.
If the new pane is cracked then you can seal it with a solvent-based glass glue or
replace window pane silicone caulk prior pressing it into the sash. In other cases, you'll need to apply putty over the crack to form an airtight seal and keep water out. When the putty dries and the film is oily, wipe it off the glass with the help of a rag. Allow it to dry completely prior to painting. If you paint before the putty has completely dry, it won't create a strong seal and may be leaking or discoloring over time.
Paint
If you've experienced a broken window pane, you may be worried about the expense of replacing it. But the truth is that replacing one glass pane does not have to break the bank if you do it yourself. In fact even windows with double panes can be replaced at less than the cost of an expert.
First, if you're working on a large-sized window, make sure that it is securely attached to the frame. This task can be made relatively simple and quick with the appropriate tools and techniques.
When you are ready to start taking down the old window pane. Take out the metal glazing points that are attached to it. These are tiny metal triangles which act as "nails" that hold the window in the frame. They are buried beneath a bead or glazing putty that sets to form solid wedge that holds the wood frame securely in place and hides the sharp edges.
After taking off the old pane clean the frame and the wood. Scrape off any old paint, and sand the rabbet grooves where the glazing points were placed. These should be sanded to bare wood so that you can paint them the same color as the rest of the frame. After the sanding process, apply a coat of flax oil on the wood that is not sanded down to prolong its life.
Then, take measurements of the dimensions of the window opening. It is necessary to measure the vertical and horizontal dimensions of the entire opening, as well as the thickness.