b'CLASS A ROOFSfire risk, it represents only one aspect of roof design.Roof ConsultingClass A testing does not evaluate wind uplift resistance, impact resistance, water management, thermal performance, inte-rior fire resistance or long-term durability. These attributes are governed by separate standards and design considerations.Becauseroofassembliesareoften modifiedtosatisfymultipleobjectives, treating Class A as a comprehensive indi-cator of performance can be misleading. Changesmadetoimproveoneperfor-manceattributemayinadvertently compromise another if the system is not evaluated holistically.THERMAL BARRIERS:WHAT THEY DO AND DONT DOThermalbarriers,commonlygypsum-based boards, appear frequently in Class A roof assemblies. In some configurations (think: combustible decks) they are essen-tial to achieving a Class A rating. In others, they are optional or absent. A thermal barrier contributes to a Class A rating only if it appears in the tested assembly. Adding a barrier where one was Roof Condition Assessments & Surveysnot tested does not automatically improve Roof System Design & Contract Managementfireperformance,justasremovingone Green Roof Design Warranty & Maintenance Reviewfromatestedassemblymayinvalidate Infrared Thermographytherating.Often,they aresimplythere Roof Access & Fall Protection - Design & Testingto protect the insulation from the heat of Roof Asset Management & Capital Planninga roofing torch and may not represent a RCABC Approved Observerstrue Class A assembly.AUTHORITY AND RESPONSIBILITY: Creative Thinking Practical ResultsWHO DECIDES, ANDWHO IS ACCOUNTABLE Vancouver 604-738-0048Victoria 250-386-7794rjc.caMostClassAissuesarisenotfromNanaimo 250-716-1550 Kelowna 778-738-1700thestandardsthemselves,butfrom www.rcabc.orgl19'