This hospital Owner in the mid-Atlantic region experienced complete roof failure within five years of installation. Components within the roofing assembly had debonded, warped, twisted, cupped, and distorted causing the roof no longer drain properly and left the Owner fearful that large portions of the roof would fail and blow off in a storm event.
During the course of the evaluation thermography, roof cores, moisture meters, document review, and visual inspection techniques were used to demonstrate a number of defects in not only the design of the building but in the installation of various roofing components.
The installing contractor had claimed that the building’s mechanical system was solely responsible for pressurizing and damaging the roofing materials to the point of failure. The Owner had claimed that there must have been a number of defects in the installation of the roofing system which caused the system failure.
During the course of the forensic evaluation it was demonstrated that the mechanical system was not responsible for the failure of the roofing system; however it was determined that defects in the design and construction of other building components such as the structural steel heliport, the roofing air/vapor barrier and roofing components contributed to total system failure. These findings coupled with significant workmanship issues led to the premature failure of the roofing system.
- The importance of coordination of the various design disciplines and how building failures are not necessarily caused by the obvious issues.
- The critical importance of airtightness in buildings and how to ensure that the roof wall interface is constructed air and water tight.
- To review the steps in evaluating a failed roof system as part of an insurance claim.
- To demonstrate how multiple failures either in design and construction work together to magnify and turn small problems into a major failure.
Timothy Mills P.E., LEED AP, Certified Infrared Thermographer, ABAA Field Auditor
TAM Consultants, Inc.
TIMOTHY MILLS, president of TAM Consultants, brings over 30 years of experience as an engineer, building envelope specialist, and roofing systems consultant for the built environment. Mills is also a licensed field auditor, instructor, and speaker for the Air Barrier Association of America (ABAA). Project types include commercial, federal, municipal, educational, institutional, single-and multifamily residential, historical, industrial and manufacturing facilities, laboratory, parking, green buildings, and retirement facilities. Mills is a frequent speaker on building envelope, forensic issues, and roofing systems. He has spoken at numerous ABAA conferences and has appeared as a guest lecturer at Penn State University.