OAHU 2022: A Burning Question: Fire Testing Of A Window Wall System With Spray Foam Insulation

The 21st Annual Hawaii Winter workshop is intended to improve your skills and knowledge of design, rehabilitation and forensics professionals.  Join us January 27-28, 2022.
More information and registration here.

Session Overview: A Burning Question: Fire Testing Of A Window Wall System With Spray Foam Insulation

In recent decades the use of unitized glazing systems has become increasingly common especially for high-rise construction. The opaque panels in unitized glazing systems have traditionally been insulated with mineral wool insulation installed within the aluminum frame behind a spandrel panel.

Increasing code requirements for energy efficiency of opaque wall assemblies has led to the common practice of providing an additional layer of insulation inboard of the unitized glazing system. In colder climates, however, the practice of insulating inboard of the unitized glazing systems raises the concern of condensation on the surfaces of the glazing system now shielded from exposure to the interior heat source. This risk is further increased if the assembly inboard of the unitized glazing system is not airtight and the interior insulation is not in continuous intimate contact with the interior face of the unitized glazing system. The application of spray foam on the inboard face of glazing systems has been used in recent years as one means of mitigating the risk of condensation.

The use of foam insulation as part of building enclosures has received increased scrutiny in recent years and numerous envelope assemblies have been successfully tested to CAN/ULC S134 or its US counterpart NFPA 285. However, most of these assembly specific tests have been performed on stud wall assemblies. This presentation will outline the testing of metal panel spandrel with interior spray foam insulation and demonstrates how these assemblies can also meet the requirements of these standards.

Learning Objectives:

• Understand the thermal performance shortcoming of unitized glazing system spandrel that leads to the use of additional interior insulation and why spray foam insulation help reduce the inherent risks of condensation in cold climates.
• Review the perceived risk of the use of spray foam insulation as it relates to fire, the requirements of the CAN S134 standard and how it compares to NFPA 285.
• Explore the challenges of testing a unitized glazing system under the requirements of CAN S134/NFPA 285.
• Assess the performance of the assembly, understand the results and their implications

This session will be presented by Stéphane P. Hoffman, M. Arch., M. Eng., P. Eng.