b'Cold Storage FacilitiescantravelbyHVAC-drivenairdrain, refrigeration pipe, plumbing pressure.Thehatsandflutesofvent, expansion joint or mechani-a metal roof deck make great air- cal penthouse, spray foam should flowchannelsbetweeninteriorbe applied to the metal deck flutes spaces of a building. for the same one to four feet at The metal roof deck, and every- atemperaturechange.Inplaces thing underneath it, typically is thewheremetaldeckhasbeencut responsibility of another trade. Butfor penetrations to pass through, when constructing a roof system,such as a plumbing vent, the hole you can do some things to make itshould be completely filled with as resistant to air flow as possible.sprayfoamaroundthepenetra-In the detail in Photo 1 on page 9,tion, providing a solid air seal. All there is a change between the refrig- thispreventstherooffrombe-eratedloadingdockandrefriger- coming an air conduit and leading ated production area.to condensation or ice issues.The air-seal detailing includes: It is also important to address 1. Premanufactured polyethyl- concrete decks over cold interiorene foam closure strips setenvironmentfacilities.Concrete in butyl sealant within thedecks lack flutes to pass air. How-metal deck flutes ever, a common design choice is Figure 1: A detail of a roof system air-stop detail 2. Closed-cellsprayfoamap- to use low-rise foam adhesives to pliedandthentrimmedassemble the roof system. In this flushinthedeckflutestocase, the foam ribbons can act as bothsidesofthedivid- air channels within the layers of ing walltypically one tothe roof. To prevent this, use full four feet to either side of aribbonsoffoamappliedacross wall where the temperatureanewlylaidboard,alongwith changes the standing S foam pattern as 3. Thesingle-plyroofmem- called for in wind design, which brane brought down to theprovidesaircutoffs.Thesame metal deck and set in butylguidanceappliestoconcrete sealant, along with the insu- decks and metal decks where all lation boards, providing thepenetrationsthroughthedecks mechanical restraint to keepneedtobesealedairtightwith the membrane on the deckspray foam.in place along with the butyl Regardlessofroofdecktype, 4. Themembranecontinuedanother critical place for air-seal over the top and heat-welded details is at the roof edge. Wheth-Using closed-cell spray foam iner it is a parapet, gravel stop, gut-the metal deck flutes is invaluableter or something in between, they in this and other areas of a roof toall need air-seal details for the roof keep air in its intended place. Fig- system to function satisfactorily. ure 1 shows a CAD cross-sectionThe exterior air seal should be re-of this air-stop detail. dundant (more than one seal) so Any time there is a penetrationif one of the seals fails over time through the deck, such as a rooforbyworkmanship,thereisa backup. Typically, this means one Figure 2: An edge air-stop detail. sealontheexteriorfaceofthe wall and one seal on top of the wall. The more difficult place to NOW make this air seal is on the outside AVAILABLEA NEW ROOFING face. When the building exterior IN BULK FROMASPHALT WITH A LOWER EVT WHICHtypically is composed of insulated REDUCES FUMESBy BITUMAR AND ODOUR. metal panels, it will be a corrugat-ed profile with a galvanized-steel 11155 St-Catherine Street East POSI-SLOPEHighly Specialized in Tapered Engineering cap on the wall. Both scenarios Montreal-East, QCH1B 0A4Simplied Installation make detailing difficult.Tel. : 514 645-4561 PIONEER IN Factory-Mitered Modules To make a seal using a single-ply bitumar.comColour Coded Drawings and PackagingITS FIELDTrained Field Technicians membrane, use 3/4- to 1-inch-wide ZEROODOUR 40 %Well Polished Design Team self-adhering butyl tape. Apply the 35 % tape continuously, butting the endWhen cold 30 %of the roll tight to the next roll. On % of fumes in the air 75 % Reduction Up to 177C 25 %the outside face of the wall, use a75 % less fumes than 20 % regular roofing asphalt 15 % termination bar or metal cleat onBURPAK ZERO contains an10 % the membrane by passing the fas-odour suppressant which 5 % Regular BUR teners through the butyl tape un-combined with a lower0 % ZEROtemperature of installation,93 121 149 176 204 232* 260 288** 316C derneath, creating a field-fabricated minimizes asphalt odour Temperature compression seal. The seal on topZero complaint on odour * Theidealviscositytemperatureistypicallylowerby23Cfor of the wall should be compressedBURPAKZEROwhencomparedwithregularroofingasphalt. SERVING ROOFING CONTRACTORS ACROSS CANADA SINCE 1982 Complaints are timeTherefore,thereisnoneedforthekettletemperature by any edge metal used. If mechan-Mississauga | Peterborough | Surrey | Montralconsuming and reducetoexceed232CwhenusingBURPAKZERO.productivity on job sites **MaximumtemperatureofakettleasperASTMD312. www.posislope.com | info@posislope.comical fastening is used on top of the 10ONTARIO ROOFING NEWSISSUE 4 2019/2020 THE ONLY SOURCE FOR PROFESSIONAL ICI ROOFING CONTRACTORS IN ONTARIO ORN'