Issue link: http://alpine.uberflip.com/i/543824
G O O D CO N N E C T I O N S | S U M M E R 2 0 1 5 6 BUILDING CODE UPDATE Changes in the 2015 International Codes and TPI 1-2014 Standard Affect the Truss Industry By Jared Yates, P.E., Engineer, Alpine T here are several important changes in the recently updated International Building Code (IBC) and International Residential Code (IRC) – IBC 2015 and IRC 2015, respectively, that impact the truss industry. Check www.iccsafe.org/about-icc/overview/ international-code-adoptions/ or www.iccsafe.org/gr/Documents/ stateadoptions.pdf to determine which code applies to your local jurisdiction. Alpine's IntelliVIEW versions 15.01.01 and later and TrusPlus 6.5.21 or later offer IBC 2015 and IRC 2015 as available options. IBC and IRC have both officially adopted the latest SPIB Southern Pine lumber values. Once the National Design Specification for Wood Construction 2015 lumber set is available in IntelliVIEW, it can be selected regardless of inventory materials or code selection to ensure you have the most current lumber values. ASCE 7-10 is again the referenced loading standard, as it was in the previous version of the IBC and IRC codes (2012), so there are no changes with regard to loading. Changes Affecting Truss Designs There are four changes in the ANSI/TPI 1-2014 National Design Standard for Metal Plate Connected Wood Truss Construction that could affect truss designs: 1. A 0.3 factor was added to the calculation of the actual compression stress perpendicular to the grain (fc-perp) at bearing joints 2. Creep factors have been increased to 2.0 and 3.0 for dry and wet service conditions, respectively 3. An alternate CSI equation for plate moment capacity was added to 2x trusses 4. A plate moment capacity check for System 42 splice plates has been added TPI 1-2014 section 7.3.8.3 added a 0.3 factor to the fc-perp calculation to check for buckling perpendicular to grain. This is a modification of the calculation added in TPI 1-2007 and may impact deeper members, such as 2x8 and larger depths that are not supported at intermediate points along their depths. Full height blocking reinforcement could be required to prevent buckling at bearings where it previously was not required based Recent code changes may impact truss designs and software programs.