b'Drainage the roof of water after it reaches a certainlevel.Overflowdrainscan alsobeplacedbesidetheprimary drainsorevenlyspacedalongthe roof perimeter for added protection.Common Pitfalls for Roof Drainage Poor Location of DrainsUnlessyoureIndianaJones, locatingdrainsshouldntrequire secretmapsorastronomy.When drains are located at the high point of the roof deck, the result will be standing water. Depending on the depthofwaterandifthereisfa-vourable weather, evaporation can occur quickly or water may remain for a long period of time. Water is typically considered ponding if it re-mains standing on the roof for more than 48 hours after weather condu-civetodrying.Inaconventional roof assembly, where the membrane is exposed, the membrane manufac-turer may void a new roof warranty.Rooftop Equipment ObstaclesRooftopequipmentcanblock drainage paths by acting as a barrier for water flow. Concrete pavers used for walkways or as setting surfaces for equipment can also block drainage paths. The result of these obstacles is water that cannot drain efficiently and locally pools at critical locations.Dirty SnowballsWhendirtanddebrisbuild around drains or gain access to the drainpipes,blockagecanallow water to back up on the roof. The presenceofwatercanencourage unwantedwildlifeandvegetation Roofs shouldnt require skates. Photo courtesy of W. Allen Partners. contributing to the debris, creating a snowball effect. 87 Bakersfield St., Toronto, Ontario, M3J 1Z4 Tel: 416-787-0649 E X P E R T S F F O R YO U RFax: 416-787-0640 Email: service@crawfordroofing.caE X P E R T S O R YO U RE X P E R T S F O R YO U Rwww.crawfordroofing.ca B BUIL I DI G G ENVELO P EB U I L D I N N E N V E LO PEUILD NG ENVELOPEIndustrial Commercial Institutional Roofing SolutionsBUILT-UP ROOFINGBUILT-UP ROOFINGBUILT-UP ROOFINGBUILT-UP ROOFINGMODIFIED BITUMENMODIFIED BITUMENMODIFIED BITUMENMODIFIED BITUMENSINGLE-PLY MEMBRANESINGLE-PLY MEMBRANESINGLE-PLY MEMBRANESINGLE-PLY MEMBRANESUBGRADE MEMBRANESSUBGRADE MEMBRANESSUBGRADE MEMBRANESSUBGRADE MEMBRANESTRAFFIC COATINGTRAFFIC COATINGTRAFFIC COATINGTRAFFIC COATINGCOCNOENSETSOTGOAG RAO ROOFOINFIGN G CONESTOGA ROOFI RI G COMMEMRCEIRACLI,A INDUST N L, COM L, INDURSITAL,A - PMI Programs- Modified Bitumen- Built Up SystemsCONESTOGA ROOFINGCO IN TITTUTIONAFL AT ROOFINGINS MERCIAL AL FLL AT STRIAL,GM TISTU ION , INDU ROOFIN- Metal Roof Systems- Waterproofing- Restoration INSTITUTIONAL FLAT ROOFINGTF:TF:1-888-518-7663conestogaroofing.com1-888-518-7663- Emergency Services- Roof Anchors- Single PlyTF:1-888-518-7663 conestogaroofing.comCOMMERCIAL, INDUSTRIAL, conestogaroofing.comINSTITUTIONAL FLAT ROOFINGCONESTOGA WATERPROOFINGCONESTOGA WATERPROOFING- Roof Top Decks- Sheet Metal- Inverted(a division of Conestoga Roofing)TF:1-888-518-7663 conestogaroofing.com(a division of Conestoga Roofing)CONESTOGA WATERPROOFINGCOMMERCIAL, INDUSTRIAL COMMERCIAL, INDUSTRIAL (a division of Conestoga Roofing)ABOVE/BELOW GRADE WATERPROOFING ABOVE/BELOW GRADE WATERPROOFING COMMERCIAL, INDUSTRIAL CONESTOGA WATERPROOFING T:T:519-620-1515conestogawaterproofing.com519-620-1515conestogawaterproofing.comABOVE/BELOW GRADE WATERPROOFING (a division of Conestoga Roofing)T:519-620-1515conestogawaterproofing.com331 Sheldon Dr, Cambridge, ONN1T 1B1COMMERCIAL, INDUSTRIAL ABOVE/331 Sheldon Dr, Cambridge, ONN1T 1B1BELOW GRADE WATERPROOFING331 Sheldon Dr, Cambridge, ONN1T 1B1Committed to Safety, Quality & Service for 40 yearsT:519-620-1515conestogawaterproofing.comServices Fully Bonded & Insured 331 Sheldon Dr, Cambridge, ONN1T 1B114ONTARIO ROOFING NEWSISSUE 4 2023/24 THE ONLY SOURCE FOR PROFESSIONAL ICI ROOFING CONTRACTORS IN ONTARIO ORN'