Whether you have a new or old home with a basement, you may or may not need to worry about the water pipes freezing. Water pipes freeze when the air around the pipes is extremely cold. You can prevent frozen pipes by understanding where pipes may freeze and what you can do to prevent frozen pipes.
If you have an unheated basement, the pipes in the basement are at risk for freezing if the temperatures drop below 20 degrees Fahrenheit for long periods of time. However, pipes can freeze when temperatures drop below freezing if cold air blows across the pipe. Even if you have a heated basement, but cold drafts coming from a broken window or a window with a bad seal that lets the cold air blow in on the water pipe, your pipe can freeze. Areas where cables or other wires come into the house can cause a draft in the basement also.
Basement Crawl Spaces
Generally, crawl spaces are not insulated and have a dirt floor. Water pipes in crawl spaces are at risk for freezing. You can have a heated basement, but the cold air in the crawl space will stay colder. When outside temperatures fall below 20 degrees Fahrenheit, the pipes will freeze unless you take preventive measures.
Outside Basement Walls
Pipes that are near outside walls can freeze. The outside walls in a basement or even on the interior of the living space get cold during extremely cold temperatures. If the temperatures drop below freezing and stay that way for long periods, the pipes near the walls can freeze.
Water pipes in a basement, whether or not it is heated, should have insulation wrapped around the pipes to help prevent freezing during the winter and sweating or warming during the summer. The insulation stops the heat from inside of the pipes from being transferred to the freezing air, which slows or can stop the pipes from freezing. If you have cracks or holes in the walls or in windows, you need to seal up the holes or cracks to keep the cold air out. Pipes should be rerouted away from crawl spaces and outside walls that get extremely cold if the pipes cannot be insulated or keep freezing after installing insulation. If the crawl space has vents, the vents need to be closed from fall to spring.