Breaking glass is a loud process, but it doesn't have to be if you break the glass carefully. Whether you're trying to get into your locked house without alerting your neighbors or wish to demolish an unneeded sheet of glass quietly, it's possible to break the glass into small pieces with very little noise by using a few common household items.
Cover the entire sheet of glass with duct tape so that no glass is visible. If you can access both sides of the glass, cover both sides.
Lay several layers of thick blankets directly below the glass. If the glass is in a window, line the blankets below the window. If you can move the piece of glass, set it on a pile of blankets in an open area.
Place a thick pillow against the glass and tap it gently with a hammer. This process will break the glass, but because the duct tape is holding it together, it won't be able to fall and create noise. If small pieces do manage to fall, the soft blankets below will absorb the sound.