b'BUILDING CODEFLEXIBILITY IN ROOF DESIGNPA R T 4 : S P E C I F Y I N G C O D E - C O M P L I A N T M E M B R A N E R O O F SBY JAMES KLASSENT his is the fourth part of a multi- InformationCentre(BuildingCodeit also means you are free to do more. part series on the Building CodeRequirements). Roofdesignandconstructionmust and roofing: In the third article of this series onthereforeoperatewithinthestated Part 1: Understanding the the British Columbia Building Code, welimitations of the Code.BC Building Code tackled the question of design respon- The Building Code is also a perfor-Part 2: The Building Code and wind sibility. Now, we discuss and apply themance-oriented document. That means avenues for roof design available in thethatwhileyouwillfindprescriptive Part 3: Roof Design: from Building Code. Our focus is on Part 3language in it (well explore some exam-Code to specification buildings. Well also explain the bene- plesshortly),eachprescribedcompli-Part 4: Flexibility in roof design fits and limitations of each avenue andance path supports the overall perfor-answersomequestionsabouttypesmance objectives of the Code. Again, You can find these articles in bothof roofs for which the Code does notthisbroadobjectiveoffersfreedom the printed and digital editions of thisprovide concrete guidance. within the boundaries set by the Code.magazine (the digital version is availableFinally, it is important to remember throughourwebsite:www.rcabc.org/ Freedom within limits thatallroofs,regardlessofhowthey publications).Youcanalsowatchtheare designed or the materials they will video presentation, Blown Away: CodeLets review some basic concepts beforebebuiltfrom,mustbeabletoresist wegetintothepracticalstuff.First,upliftingforcesgeneratedbywind RequirementsforMembraneRoofs,itsimportanttorememberthatthetheCodecallstheseSpecifiedWind thataddressesseveralarticlesinthisBuildingCodeestablishesminimumLoads (SWLs). And thats a good thing. series. To find the link, go to the Roofingrequirements. That means you cant doAfter all, who wants a catastrophic roof Practices Manual (RPM), Division E: less than what it says you must do, butfailure on their resume?18lROOFINGBC l SPRING 2022'