Water Leakage Investigations
Paul Beers made a welcome return to the Everything Building Envelope podcast, following an extended hiatus as he helped clients recover from previous hurricane seasons. With water damage on his mind, Paul invited Jason Bondurant for an extensive discussion on the challenge of investigating water leaks. Jason is a senior consultant with GCI Consultants, currently conducting forensic investigations to solve problems with existing buildings, many of which originate with water intrusion.
Paul and Jason possess formidable knowledge and skills in multiple aspects of water intrusion issues and all parts of the structure that may be subject to leakage. For this episode, they focused on windows and doors.
Water may infiltrate a building undetected over time, or as a result of a storm event. No type of structure is exempt from the threat of water intrusion, whether newly constructed or existing, and it tends to be unpredictable in its pathways, with each incident unique.
Windows and doors are required to pass a host of laboratory tests in order to meet the building code certification standard. Testing for the structural strength of windows and doors often exceeds the design rating for the component; for example, a window rated for 100 psf (pounds per square foot) may be subjected to structural testing in the laboratory up to 150 psf.
The bar is lower for water intrusion tests. The requirement for testing resistance to water infiltration is to measure to 15 percent of the design rating. Laboratory tests don’t simulate field conditions. Once the window is installed, a field test is conducted, but the requirement is lower than the laboratory test, by as much as two-thirds.
As a result, building owners are often assured that they have a window or door that can withstand hurricane force winds, but are unaware that the window or door is not rated to resist water penetration up to those hurricane force winds.
Tracking the Intrusion
Field testing for newly installed window and door assemblies must be conducted within six months of installation. After that time period, testing is usually initiated as a result of an existing problem, triggering a systematic diagnostic process to find the source of water leakage.
Typically, the investigation takes place after a contractor has tried — and failed — to fix the problem. These remediation attempts can complicate the diagnosis, since often the attempted remedy is in conflict with the design concept. Jason gives the example of openings intended to drain, that are mistakenly sealed by a contractor.
Eight steps are set out in the “Standard Guide for Evaluating Water Leakage in Building Walls”, also referred to as the ASTM (American Society for Testing and Materials) E2128. The process includes gathering relevant documentation, service history, evaluating the design concept, conducting a site inspection, and investigative testing. Jason finds following this step-by-step methodology tenaciously results in a high rate of success for water leakage investigations.
The eight-step process in ASTM E2128 encourages qualitative analysis, where the investigator looks for patterns when examining the evidence of leaks, combining research, visual observation, and expertise to evaluate the likely source. Investigative testing is then carried out on representative components of the building to see if the theory is correct.
With this approach, destructive testing — where parts of the building need to be dismantled — is limited to a few strategic locations. Generally, interior finishes are disturbed during investigative testing for water intrusion through window and door assemblies.
Listen to the full conversation between Paul and Jason at the Everything Building Envelope podcast and remember to subscribe while you’re there, for more discussions between members of the team at GCI Consultants and other experts in the building industry.
For more information on water leak investigations, visit www.GCIConsultants.com or call