b'Ongoing maintenance is required to keep drains clear of debris. Any building operator can check the roof drainage on a regular basis by removing leaves, dirt and garbage from around the roof drains surface.MechanicalGood,Badroof was designed for them, in-and Ugly Parts of the Draincluding overflow drains. On the Assembly same note, they should not be Highdrainperimeterremoved if already incorporated guards, mesh covers, flow con- into the roof system, as the in-trol devices and retrofit drain in- creased flow rate can overwhelm serts are examples of mechanicalmunicipal sewers. So dont re-parts that can obstruct drainage.movethemifyouwouldstill Whenusedasintended,theylike to go to your local beach!willenhancetheroofsdrain- Drain Relocationage. However, flow control withAs mentioned in the previ-nooverflowdrainageordrainous section, existing drains that screens/membraneclampingaresetathighpointsofthe rings lacking clear drainage canstructural deck can cause stand-holdwaterbacktothepointing water. Relocating the drains that things turn ugly. Excessiveto low points of the roof deck waterimpactstheroofsper- canpromotedrainage.This formanceandsafetyinworst- would require plumbing repairs casescenarios. and additional or repositioning of drain pipes.Retrofit Options Add Drains or ScuppersMaintenance Additionaldrainscanbe Ongoingmaintenanceisadded totheroofarea and,if requiredtokeepdrainsclearfeasible,newdrainpipescan of debris. Any building opera- connect into the existing pipes. tor can check the roof drainageAgain,plumbingrepairsbya on a regular basis by removingprofessional would be required. leaves,dirtandgarbagefromNotethataddingadditional around the roof drains surface.drainsbeyondtheoriginalhy-Ballast guards and drain screensdraulicloadcapacityshould preventdebrisfromenteringnotbecompletedunlessall the drain pipes themselves, butplumbing lines to the sewers are debris can build up around thechecked to be able to take the guards and, if not cleared regu- increasedload.Ifnot,interior larly,cancauseblockage.Thisplumbing pipes can burst and/can be outsourced to a contrac- or back up into the building.tor, and if modifications need toScupperdrainscanbein-be completed, then the contrac- stalledalongtheexteriorpe-tor can implement them. rimeter of the roof and used as PreventorRemoveMe- overflow scuppers for emergen-chanical Obstructions cies, or at roof level to act as a There are drain fittings thatconsistent drainage outlet.canbeinstalledontheinsideAdd Sloped Infill ofdrainpipes,whichareanSlopecanbeintegratedei-optionwheninstallingnewther during construction of the insertdrainswheretheinte- roof or as surface retrofits. rior plumbing is not accessible.Lightweightconcretewith However, these reduce the flowbuilt-inslopedinsulationcan rate from the original drain duebe installed during a roof retro-tothereductioninplumbingfit. This can remain intact over pipediameter,andmayresultmanyroofmembranereplace-in the same roof being under- mentprojectsastheconcrete designed for the hydraulic loadwill protect the insulation from required by codes. These devicesdeterioration. can be avoided by accessing theAs previously mentioned, a drains from the underside andcommonpracticeistouseta-instead installing fittings on thepered materials integrated into exterior side of the pipes. the roof during construction.While new buildings requireInsituationswhereroof-flowcontrols,thesedevicestop equipment blocks drainage should only be installed if thepaths, crickets created by sloped ORN THE ONLY SOURCE FOR PROFESSIONAL ICI ROOFING CONTRACTORS IN ONTARIO ONTARIO ROOFING NEWSISSUE 4 2023/2415'