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• I • TECHNICAL BULLETIN SIMPSON Code-Compliant Guardrail Post Connections trong-Tie Guards: What the Codes Require How does load or deflection at the top of a guard post The 2015 International Residential Code(IRC)and 2015 relate to a connector at the base of a guard post? International Building Code(IBC)each have specific requirements As a result of the large leverage arm of Deflection, for the design,construction and use of guards.Some of these a guard post,the tension force in the top of post — requirements are shown below. post-to-deck connector will be much 200 lb. --IN, larger than the force at the top of the i I When is a guard required? post.Similarly,any deflection at the post- t "Guards shall be located along open-sided walking surfaces, to-deck connector will result in amplified t including stairs,ramps,and landings,that are located more than deflection at the top of the post. For a i 30 inches measured vertically to the floor or grade below..." 36"post connected to a 2x8 deck joist, a 200 lb.force at the top will result in t IRC 2015,Section R312.1 about an 1,800 lb.force in a connector "Guards shall be located along open-sided walking surfaces...that located 2"from the top of the joist.A 1/4" are located more than 30 inches measured vertically to the floor or of deflection in this connector will result in t grade below..." over 2"of deflection at the top of the post. Deflection, t t connector t ' IBC 2015,Section 1015.2 t Do the Simpson Strong-Tie =��_� t details address load applied Connector I If a guard is not required because the deck or porch tension t il is 30 inches or less above the floor or grade, does the in all directions? guard have to be code compliant? The details in this technical bulletin address an outward force on the guardrail.An additional All guards must be designed and constructed in accordance connector can be installed on the lower bolt to resist an with the governing building code,including guards that are inward force. not required.The general public expects all guards to perform and falls resulting from guard failures can cause serious injury Why have the code requirements changed? regardless of the fall height. The 200 lb.point load requirement in the code is not new. What is the guard height requirement? However there has been an increased focus on this requirement in recent years.Research and testing conducted at Virginia Tech In the IRC,"guards at open-sided walking surfaces,including on post-to-rim-joist connections indicated common bolted or lag stairs,porches,balconies or landings,shall be not less than 36 screwed connections to a rim joist alone did not meet the load inches high..." requirements in the code. IRC 2015,Section R312.2 In the IBC,"required guards shall be not less than 42 inches Why the Simpson Strong Tie solution? high..." The connection details shown have been designed to meet the requirements in the building code.Simpson Strong Tie also IBC 2015,Section 1015.3 performed testing on several full-scale assemblies.Some of this testing is summarized in the table below. How much force must a guard be capable of resisting? For one-and two-family dwellings,both the IRC and IBC require guards be designed to resist a single concentrated load of 200 lb. applied in any direction at any point along the top. Post-Fastening Average Test Average Connector Deflection at Assembly Ultimate IRC 2015,Table R301.5; IBC 2015,Section 1607.8 2001b. Outside rim joist, 635 lb. 23/4" What is the allowable deflection of a fully fastened to joist loaded guard post? DTi2 Outside rim joist, 5 The building codes do not contain deflection limits for guards fastened to blocking 650 lb. 1/e' , however the International Code Council Evaluation Service Outside rim joist, , Acceptance Criteria 273 for Handrails and Guards(AC273)places 790 lb. 1 h" fastened to joist reasonable limits on tested assemblies.The maximum permissible HD3BHDG2 deflection in AC273 for 36"-high guards is 3". Outside rim joist, 655 lb. 11/2" fastened to blocking 1.Applied load and measured deflection shown are at top of post. 2.HD3B values based on testing with a lower-capacity holdown. "The 2009 and 2012 International Residential Code and 2009 and 2012 International Building Code each have similar requirements. For simplicity,this document references the 2015 edition of each code. This technical bulletin is effective until December 31,2019,and reflects information available as of July 1,2017. This information is updated periodically and should not be relied upon after December 31,2019. (800) 999-5099 Contact Simpson Strong-Tie for current information and limited warranty or see strongtie.com. strongtie.com ©2017 Simpson Strong-Tie Company Inc. • P.C.Box 10789,Pleasanton,CA 94588 T-C-GRDRLPST1 7 7/17 exp.12/19 '2_Bk 26