Plumbing water lines can freeze and burst when the water inside the pipes freezes and expands, causing pressure on the walls of the pipe. Inadequate insulation, exposure to freezing temperatures, poor hot water circulation, and vacant or unoccupied homes can contribute to frozen and burst pipes. To prevent this, it is important to properly insulate pipes, maintain a consistent temperature, and keep a trickle of water flowing through the pipes during cold weather. Immediate action should be taken if you suspect your pipes are frozen.