WATER BASICS:

When water freezes, it changes phase from a liquid to a solid and expands in volume by approximately nine (9) percent. Typical piping systems are relatively "rigid" (inflexible) as most components are not physically capable of expanding to accommodate the volumetric increase, commonly resulting in the failure of one or more components. Pressures approaching 10,000 PSI (pounds per square inch) have been recorded within ice-filled piping systems, thus most plumbing components are prone to failure upon exposure to the right conditions. During laboratory testing conducted by McGreal Forensic Engineers PC it was observed that most component failures occurred at points at a distance from the origin of the ice nucleation (formation). When ice freezes within a pipe it acts like a "piston", exerting pressure on both the pipe as well as the adjacent water. The pressure delivered to the water is then transmitted to all points that are hydraulically connected. Components within either heated or unheated spaces may fail as a result of water-filled piping being exposed to freezing conditions.


COMMON CAUSES OF "FREEZE-TYPE" PIPING FAILURES:

Common conditions that may result in "freeze-type" piping failures include but are not necessarily limited to the following:
• Thermostat set too low;
• Failure or malfunction of one or more HVAC (heating) systems or components;
• Insufficient amount of insulation;
• Displaced/incorrectly placed insulation;
• Wet/degraded insulation;
• Incorrectly specified/installed HVAC system;
• Construction defects;
• Building openings (open windows/doors, possibly transient);
• Extreme/unusual weather conditions.


WHY WATER-FILLED PIPING COMPONENTS CAN FAIL WHEN SUBJECTED TO FREEZING CONDITIONS:

When water freezes, it expands. That is why a can of soda will burst in your freezer. When water freezes in a pipe, it expands in the same way. When a pipe bursts, the break does not necessarily occur at the exact spot where the ice blockage is located. Ice expansion will exert pressure against the pipe wall but also pressurizes the water trapped between the ice and a closed valve or fixture. As the water continues to freeze and expand inside the pipe, it causes the trapped water to continue to increase in pressure. The increased water pressure may cause a pipe to burst in a location where there is no ice blockage. After the pressure exceeds the strength of the piping component, failure will occur.


ABOUT McGREAL FORENSIC ENGINEERS PC/
TIMOTHY R. MCGREAL, P.E., ME, FPE, CFEI:

This video was created in conjunction with a Whitepaper entitled : " Analysis of Freeze-Related Fire Sprinkler System and Water-filled Piping System Failures" to help insurance and law professionals understand some of the ways that fire sprinkler systems may fail and can cause or contribute to property loss, injuries, and/or loss of life. The paper may be downloaded at www.mcgrealforensic.com. In our experience, many failure modes are frequently misunderstood and/or not identified by the experts and engineers that have been retained to investigate said failures. Mr. McGreal has performed more than 1,100 investigations for insurance and legal clients on claim sizes up to $500,000,000 within the Continental U.S., Hawaii, Canada, and Mexico and has a Master of Science degree in Fire Protection Engineering from the Worcester Polytechnic Institute (WPI) and a Bachelor of Science degree in Mechanical Engineering from the Illinois Institute of Technology (IIT). Mr. McGreal is a licensed Professional Engineer (IL 062057166), and a Certified Fire and Explosion Investigator (NAFI-CFEI).

McGreal Forensic Engineers PC
2328 E. Lincoln Highway, #309
New Lenox, IL 60451
mcgrealforensic@protonmail.com
708-326-3077

www.mcgrealforensic.com

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