Month: July 2022

Desaturation Testing – Modified Bitumen Roofing Membrane

Desaturation Testing of Modified Bitumen Roofing Membrane

Manufacturing facility with several large buildings covered with granule surfaced modified bitumen (mod-bit) roofing membranes. Concerns were raised regarding hail-caused damage to the roofs. The mod-bit roofs varied in age and had numerous regions where granules were missing that were presented as examples of hail-caused damage. Our client needed to know if the roofs had been damaged by hail.  

Mod-bit roofing samples and their substrates were removed and tested in the HRT laboratory to determine if regions of missing granules were caused by hailstone impacts and to determine if the roofing samples had been damaged by hail. Samples were visually and tactilely examined by laboratory personnel and then samples were processed via hot solvent desaturation, which removes the bitumen and surfacing, allowing the reinforcements to be closely examined for ruptures or strains consistent with hail impact forces. 

Overview of property
Area presented as being related to a hailstone impact (left) and close-up (right)

Prior to desaturation, the samples and substrate taken from the roof were mounted to a panel and impact tested with various sizes of ice balls. Ice balls were frozen solid and propelled perpendicular to the test panel at free-fall velocities of similar sizes of hail to replicate worst-case impact conditions.

Sample and substrate mounted to test panel for hail simulation testing
Sample after impact testing with ice balls to simulate hailstone impacts

After impact testing, reinforcements were examined at the area of interest (See Figure 2) for conditions related to hailstone impact. The reinforcements were intact. Additionally, the area of interest was visually dissimilar to areas impacted by simulated hailstones.

Base ply reinforcement was intact at the area of interest after desaturation

Regions of the reinforcements subjected to simulated hailstone impacts were also examined after desaturation. It was determined that frozen solid hailstones of about 1-3/4 inches in diameter or larger could bruise the mod-bit roofing, which was a condition not detected in the field or during laboratory examination.

Base ply reinforcement at simulated hail impacts

Simulated Hail Impact Testing – PVC Roofing Membrane

Simulated Hail Impact Testing of PVC Roofing Membrane

Large school with numerous roof sections covered with a variety of single-ply roofing membrane types. One section covered with a relatively new thermoplastic polyolefin (TPO) membrane, several large sections covered with old polyisobutylene (PIB) membranes, and several sections covered with polyvinyl chloride (PVC) roofing membranes estimated at about 10 years old. School had been struck by hail on numerous occasions and the roof was examined for hail-caused damage. Some of the PVC roofing had obvious hail-caused damage and our client needed to know when the hail-caused damage had occurred.

Samples of the PVC roofing were removed and tested in the HRT laboratory to determine the minimum size of hail that could damage the PVC membranes and to determine what size hail would create similar size fractures in the membrane and similar dents in the insulation. Samples and substrate taken from the roof were mounted to a panel and impact tested with various sizes of ice balls. Ice balls were frozen solid and propelled perpendicular to the test panel at free-fall velocities of similar sizes of hail to replicate worst-case impact conditions. 

Overview of campus
Hail fracture on bottom of PVC membrane
Hail fracture on bottom of PVC membrane with backlighting

Based on simulated hail impact testing, the minimum size of hail that could cause similar impact damage to the PVC membranes was 1-1/4 inches in diameter. Based on a review of weather records, information gathered during our inspection, and laboratory test results, there was one specific storm that could have caused the fractures in the PVC membranes.

Impacts from ice balls measuring 1, 1-1/4, and 1-1/2 inches in diameter (left to right)
Simulated hail impacts used to compare dents in insulation

Hail-caused dents in the insulation were consistent in size and depth as dents resulting from simulated hailstone impacts made with ice balls measuring 1-1/4 inches in diameter, corroborating the hail-caused damage to the PVC roofing membranes were likely caused by hailstones measuring about 1-1/4 inches in diameter.   

Hail dent in insulation (left) and similar dent with 1-1/4 inch diameter ice ball (right)

Fire Investigator Steven Reed Joins Haag in North Carolina!

Haag Welcomes Steven Reed, IAAI-CFI, NAFI-CFI New Fire Consultant in North Carolina!

“We are very pleased have Steven Reed on Haag’s Fire O&C team,” said Edward Roberts, Director of Fire Investigation Services. “Steven Reed has more than three decades of fire investigation experience and has personally conducted over 3,000 fire investigations.”

About Steven Reed:

  • Holds multiple fire and explosion certifications, including IAAI-CFI
  • 36 years of investigative training and experience
  • Court tested and reliable. Experienced in municipal, civil, & criminal trials
  • One of 330 individuals worldwide to hold all three NAFI Certifications
  • Lead investigator in large/complex losses such as an explosion/fire at a refinery in Singapore
  • lead investigator of a commercial building fire in Oakland, CA that claimed 36 lives.
  • He has led multiple large losses at apartment complexes, commercial properties large scale manufacturing plants.

For more information or to contact Mr. Reed for your next fire assignment, please email or call 800.527.0168.

Stains on Sculptures – Multi-Disciplinary Investigation

Basic Fact Pattern

  • A mysterious repetitive staining was discovered on a marble sculptural installation within a construction work zone at a major museum in Michigan.
  • The marble pieces were sculpted using water jetting technology in Spain, after which they shipped internationally on a freight barge in partially open crate containers.
  • The staining was random in nature, but tended to appear in horizontal joints, but not vertical ones.
  • The staining would re-appear over the course of more than one year, but not always in the same locations.
  • Previous experts had speculated about possible moisture entrapment within the marble pieces and/or moisture absorption into the marble during shipping in improper containers.
Overview of Sculpture
Sculpture area under construction
Investigative Sciences Employed
  • The entire sculptural installation was 3D scanned in place in color to document the locations where the staining currently existed, in combination with the joint locations throughout the installation.
  • An infrared scan of the marble surfaces was conducted to determine if patterns of moisture and/or air migration were detectable within the joints of the sculptural installation.
  • A temperature and humidity survey was taken on a grid system within the room to determine if patterns of moisture and/or air humification were detectable within the museum room.
  • Portions of the installation materials that had not yet been installed were sampled for chemical testing, including shavings from the backside of one of the marble pieces and the supporting structural framework, attachment, and lateral anchorage elements.  Shavings of discolored marble were also collected from inside of one of the stained horizontal joints.
  • Historical data regarding the appearance of staining over time from the museum were compared to the Building Management System temperature and humidity readings obtained within the construction zone over time.
Stains between horizontal joints
Back of sculpture

Determinations Made:

  • A lack of complete environmental controls within the construction zone was causing seasonal fluctuations in temperature and humidity, affecting the absorption, release, and condensation of moisture into and out of the marble pieces over time.
  • Environmental conditions present at the time of installation of each individual piece directly affected the timing of when staining would appear within any given marble piece.  Differences between the marble pieces themselves also caused many pieces to not exhibit staining at all.
  • The white marble material contained a soluble salt impurity that was released only in the presence of bulk water.
  • Staining only occurred during the moisture condensation phase of the indoor environmental changes.  Due to variations between the conditioned front side of the sculpture and the unconditioned backside of the sculpture, vapor drive expelled the excess moisture through the joints.
  • Welded stainless steel lateral anchorage plates were embedded into gouges in the stone pieces at the horizontal joints only.  Condensed bulk water collected in the gouges, releasing the salts, interacting with the anchors and/or their welds, thereby forming the colored contaminant, which was then transported through the horizontal joints by the vapor drive, depositing the colored contaminant on the surface of the sculpture.
Involved Experts: 
  • Benjamin Irwin, PE, DFE
  • Everett Lenhart, PE
  • Matt Westrich, PE
Welded stainless steel lateral anchorage plates

Grand Design is Recalling Certain 2022 Momentum Travel Trailers

NHTSA Campaign Number: 22V442000

Manufacturer Grand Design RV, LLC

Components ELECTRICAL SYSTEM, EQUIPMENT

Potential Number of Units Affected 165

Summary

Grand Design RV, LLC (Grand Design) is recalling certain 2022 Momentum travel trailers. The 110-volt power supply wire was incorrectly wired directly into the solar inverter, which can overload the circuit and cause the power supply wire to overheat.

Remedy

Dealers will rewire the 110-volt power wire, free of charge. Owner notification letters are expected to be mailed July 25, 2022. Owners may contact Grand Design customer service at 1-574-825-9679. Grand Design’s number for this recall is 910030.

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.

General Motors is Recalling Certain 2022 Cadillac XT5, XT6, and GMC Acadia All-Wheel Drive Vehicles

NHTSA Campaign Number: 22V446000

Manufacturer General Motors, LLC

Components FUEL SYSTEM, GASOLINE

Potential Number of Units Affected 228

Summary

General Motors, LLC (GM) is recalling certain 2022 Cadillac XT5, XT6, and GMC Acadia All-Wheel Drive (AWD) vehicles. The fuel tank rollover valve may not provide a proper seal in the event of a rollover crash.

Remedy

Dealers will inspect the fuel tank and replace the fuel tank shell if the rollover valve is found to be dislodged or missing, free of charge. Owner notification letters are expected to be mailed August 8, 2022. Owners may contact Cadillac customer service at 1-800-458-8006 and GMC customer service at 1-800-462-8782. GM’s number for this recall is N222366070.

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.

Triple E is recalling certain 2021-2022 Unity and Wonder Recreational Vehicles

NHTSA Campaign Number: 22V435000

Manufacturer Triple E Recreational Vehicles

Components EQUIPMENT

Potential Number of Units Affected 371

Summary

Triple E Recreational Vehicles (Triple E) is recalling certain 2021-2022 Unity U24MB, U24IB, U24CB, U24FX, U24RL, U24TB, and Wonder W24MB, W24RTB, W24FTB, W24RL recreational vehicles, equipped with certain 2-burner cooktops. The burner control valves may become damaged, causing a gas leak.

Remedy

Triple E will work with Dometic to replace the cooktops, free of charge. Owner notification letters are expected to be mailed June 2022. Owners may contact Triple E customer service at 1-877-992-9906 or contact Dometic at recall.cooktop.22E021@dometic.com or 1-888-943-4905 or 574-389-3713. Triple E’s number for this recall is CA#10130-1.

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.

Cruiser is Recalling Certain 2022 Shadow Cruiser, Embrace, MPG, Radiance, Hitch, Twilight, and Stryker Travel Trailers

NHTSA Campaign Number: 22V433000

Manufacturer Cruiser RV

Components EQUIPMENT

Potential Number of Units Affected 2,985

Summary

Cruiser RV (Cruiser) is recalling certain 2022 Shadow Cruiser, Embrace, MPG, Radiance, Hitch, Twilight, and Stryker travel trailers. The quick disconnect fittings in the LP gas system may be cracked, causing a gas leak.

Remedy

Dealers will inspect and replace the fittings, as necessary, free of charge. Owner notification letters are expected to be mailed in July 17, 2022. Owners may contact Cruiser customer service at 1-574-206-7920. Cruiser’s number for this recall is 99.03.21.

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.

Heartland is Recalling Certain 2022 Travel Trailers

NHTSA Campaign Number: 22V432000

Manufacturer Heartland Recreational Vehicles, LLC

Components EQUIPMENT

Potential Number of Units Affected 12,285

Summary

Heartland Recreational Vehicles, LLC (Heartland) is recalling certain 2022 Cyclone, Gravity, Sundance, Big Country, Big Horn, Big Horn Traveler, Elkridge, Fuel, North Trail, Landmark, Lithium, Milestone, Torque, Trail Runner, Pioneer, Prowler, and Road Warrior travel trailers. The quick disconnect fittings in the LP gas system may be cracked, causing a gas leak.

Remedy

Dealers will inspect and replace the quick disconnect fittings, free of charge. Owner notification letters are expected to be mailed July 17, 2022. Owners may contact Heartland customer service at 1-877-262-8032. Heartland’s number for this recall is 99.01.67.

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov

Nova Bus is Recalling Certain 2019-2021 LFS and 2019-2022 LFS Artic Buses

NHTSA Campaign Number: 22V416000

Manufacturer Nova Bus (US) Inc.

Components ENGINE AND ENGINE COOLING, ELECTRICAL SYSTEM

Potential Number of Units Affected 273

Summary

Nova Bus (US) Inc. (Nova Bus) is recalling certain 2019-2021 LFS and 2019-2022 LFS Artic buses. The radiator fan’s electrical fuse holder may experience excessive corrosion which can result in an electrical short.

Remedy

Nova Bus will provide the remedy parts and service document instructions, free of charge. Owner notification letters are expected to be mailed on June 30, 2022. Owners may contact Nova Bus’ customer service at 1-800-350-6682. Nova Bus’ number for this recall is CR5259.

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.