Whether it's a neighborhood fly ball, a tree branch or old age that's caused a pane in your window to break, dealing with it can be a nuisance. Luckily, repairing broken glass is easier than you think. Keeping a few safety measures in mind, your window can look like new in no time.
In order to have all your materials on hand, measure the pane of glass that needs to be removed. Order your replacement piece already cut to size so that once the glass is out, you'll be ready to put the replacement right in. Your local hardware store or a glass store will be able to advise on the right kind of glass is best for your window, in case you aren't sure what to use.
Before you get started, make sure you have a pair of heavyweight gloves on hand. You'll need to remove the broken shards by hand, so keeping yourself protected is important. Remove the glass piece by piece. Most of the pieces will just require a little wiggling to come loose. If there is a piece that needs a bit more of a pull, consider using a heat gun to soften the surrounding putty.
You can also try pulling out the putty with your hands, taking caution not to do it too quickly as you don't want glass pieces to fall on the floor. Once all the glass is removed, take a small chisel or putty knife to remove the putty. Once the putty is removed, rub a little linseed oil onto the surface in order to prep the wood for putty to be added in again. Once the glass and putty is gone, you'll want to pry the old rabbets out of the corners of the pane, which is where the glass sits. Make sure you're still wearing your gloves as these can be sharp and hard to remove.
You will want to pick up a new pack of push points (also known as rabbets) to hold the new pane in place. Keep them in their existing spots.
Before glass goes in, it's time to handle the putty. Using a putty knife, smooth it along one edge of the window in a fast even line, keeping the layer thin, pressing into the rabbets and filling them with putty.
Take your piece of glass and wiggle it into place, applying pressure into the putty. Place a push point in the center of each side of the pane, gently pushing it in place until it's in the wood. Apply putty rope, which you'll stretch out by rolling it in your hands, around the glass edges and push it against the exposed rabbets. Run a putty knife along the glass panes, removing all the excess putty. You shouldn't be able to see any of the putty on either side of the glass if this is done correctly. If you want to paint over the panes, lets the putty sit for at least ten days to stiffen up before you spiff up your windows.