| Structural Insulated Panels or SIPs and Seismic Performance|
|SIPs are a strong structural panel building component used in residential homes and commercial buildings for the walls, roofs and floors. SIPs have a history of performance in seismic events. In particular, a number of SIP structures were located close to the epicenter of the magnitude 6.9 earthquake that struck Kobe, Japan in 1995. A review of these structures after the earthquake demonstrated that the inherent performance of SIPs in seismic events is exceptional.|
SIPs develop their shear strength from the use of outer facings of 7/16" OSB manufactured in conformance with the PS2 standard for sheathing. Each SIP wall panel is connected to base plates, top plates, and vertical boundary members with fasteners, typically 8d nails. The 8d nails provide for the transfer of the shear loads from the OSB facings to the wood plating materials while the bond of the OSB to the EPS core provide resistance for the OSB from buckling. This performance is analogous to conventionally built OSB sheathed shear walls where the OSB provides shear resistance by using fasteners to transfer shear loads to the framing members.
SIPs have been evaluated side by side with OSB sheathed conventional walls. Testing has been conducted by the leader in the development of shear wall design data for light frame walls, APA - The Engineered Wood Association. Testing consisted of building conventional OSB sheathed 2X shear walls and comparing the performance to Structural Insulated Panels.
Testing was conducted following a seismic test protocol developed by the Structural Engineering Association of Southern California (SEAOSC). The test consists of imposing a simulated seismic event to a shear wall and recording the response. The test protocol consists of 72 cycles of loading for the shear wall. The resulting loads and deflection for the conventional shear wall and the SIP wall were nearly identical.
It is recommended that SIPs are similar to conventional light frame shear walls with OSB sheathing for performance in seismic events with proper engineering of connections and load transfer.
Future research by industry is anticipated to help develop the market for Structural Insulated Panels in high seismic regions.
R-Control SIPs is a leading supplier and manufacturer of structural insulated panels throughout North America and the world. Learn more information on R-Control SIPs.
To learn more about how resist SIPs resist seismic activity please visit the SIP industry leader R-Control.
Todd Bergstrom, Ph.D. is Vice President of Technology for AFM Corporation, a company that provides technical, regulatory, and marketing support to R-Control SIP licensees throughout North America and the world.