Why pipes freeze

Low winter temperatures can cause problems to the house water management systems, especially piping. Due to its unique property, water expands as it freezes. The expansion of water in pipes creates pressure and ice blockage which in turn creates tremendous pressure inside the pipes, eventually rupturing the piping material.

Modern construction techniques and standards require contractors to protect the pipes by installing them in insulated spaces, reducing the risk of freezing. Insulation is particularly important in northern cold climates.

Pipes at higher risk of freezing are:

1. Pipes that run through exterior walls or cabinets. Poor insulation increases the vulnerability. Cracks in walls and foundations as well as utility line entry points also increase the risk of freezing.

2. Exterior installed water supply piping such as outdoor hose bibs, swimming pool supply lines, water sprinkler lines and outdoor kitchen supply lines.

3. Pipes in unheated interior areas like basements, crawl spaces, attics, garages, etc.

How to prevent pipes from freezing

Prevention methods are closely related to energy loss prevention and improvements such as:

1. Making sure your home is properly insulated.

   a. Add insulation to attics, basements and crawl spaces. Insulation will maintain higher temperatures in these areas. 

2. Sealing cracks and openings in the walls, attic, basement or crawlspace.

   a. Weather strip and caulk around crawlspace doors and basement windows; and

   b.Install storm windows over old basement windows; or

   c.Replace old basement windows with new more efficient ones.   

3. Insulate both hot and cold pipes in unheated areas such as crawl space, basement, garage, under cabinets, and inside cabinets installed along the exterior walls, etc.

4. Open cabinet doors under sinks to let warm air flow around the supply lines.

5. Close foundation vents.

6. Drain water from swimming pool and water sprinkler supply lines according to manufacturer's or installer's directions.

   Thawing Frozen Pipes

1. The first sign of frozen pipes is a drop in the water pressure.

2. If you suspect a frozen pipe(s), immediately find the whole house water shut off valve (typically located by water meter) and turn it off to reduce water pressure and minimize water leaks from the pipe(s) if it bursts.

3. As soon as the whole house water shut off is turned off, open all faucets in the house. This will eliminate the pressure from the pipes and give the ice room to expand without bursting the pipe. If for any reason it is not possible to turn the whole house shut off valve, open all faucets in the house. At this point it is a good idea to call a professional for assistance.

4. The next step is to look for frozen pipes in any area of the house that are located in the areas at high risk of freezing. A good starting point is pipes located in areas colder than the rest of the house, such as pipes along exterior walls, in basements, in crawl spaces, in attics or any other areas described at the beginning of this article.

5. Once you find frozen pipes, apply gentle heat to that section of pipe by applying gentle heat such as a hair dryer or towels soaked in hot water and wrapped around the pipe. Never use an open flame to thaw frozen pipes, as this could cause a fire.

6. If you can’t find the frozen pipes or have a pipe frozen inside a wall call a licensed plumber. They have specialized pipe thawing equipment that can help thaw the pipe without damaging the wall.