If you have a broken window, then you will want to repair it as soon as possible. Not only do broken windows counteract any climate control in your house, they are also safety and security risks for you and your family. Here is a brief guide regarding exactly what you need to do if you want to replace a broken window:

Remove the broken pane

If the glass is cracked, then you will need to manually remove the entire pane and all of the surrounding putty. The putty must be removed first in order to remove the damaged pane in one piece. 

However, if the window is entirely shattered, then you can remove the fragments one by one. It is especially important that you use safety gloves and take the proper precautions when dealing with shattered glass due to the risk posed by extremely jagged edges. After removing all the glass from the window, then you must remove the putty in the frame.

Beneath the putty, you will find glazier's points (small metal triangles) which you must remove. If necessary, use a chisel or similar tool to remove the putty. Heat may also be applied to the putty in order to soften it, if need be.

Prepare the frame

After you have removed the old putty, you will need to apply a new layer of putty to the same area. This putty should be doughy, but you might need to thin it if it isn't pliable. Linseed oil may be applied first in order to prevent putty from drying out.

You then need to acquire a pane of glass which is just slightly smaller than the frame. This is because glass tends to have imperfections and expands or contracts under changes in temperature.

Installing the new window

The new pane of glass should be carefully placed in the frame. Glazier's points should be placed on each side for stability. If the pane of glass is large, then you can add additional glazier's points at roughly 4" intervals. You will need a glazing tool to fasten the glazier's points into the putty.

Finally, you will need to even the putty out so that it looks good. Remove any excess using a rough material such as sandpaper if necessary.

If you're worried about getting hurt or not being able to do the job properly, it may be better to rely on a professional like Ken Caryl Glass Inc.