Issue link: http://digital.canadawide.com/i/1385297
Mapelastic used on the newly renovated Viaduc Sud rail overpass, Montreal, QC. Jameson House, Vancouver, B.C. Material preparation for the new Walmart roof , Victoria, B.C. J U N E 2 0 2 1 | 41 Waterproofing P H OTO G R A P H Y CO U RT E SY M A P EI ; K RY TO N I N T ER N AT I O N A L I N C .; R J C EN G I N EER S High-performing waterproofing products provide solutions to Canada's biggest projects by ROBIN BRUNET T here are more waterproofing products than one can shake a stick at; better still, they have evolved to the point where unwanted water ingress is not the threat it once was, provided the systems are carefully selected for the problems at hand. As far as Jason Guldin, associate at RJC Engineers is concerned, early consultation is the real key to successful waterproofing of roof podiums/plazas, below-grade foundation systems, and other related structures. "You don't necessarily need the most expensive system and you don't need to have intimate knowledge of every type of waterproofing material out there," he says. "I believe it's important that the consultant and client identify the problem, effectively develop the project objectives and vision, generate a practical solution, and take the time to also communicate with industry product reps and contractors." Recently RJC designed a 70,000-square-foot roof for a new Walmart at Hillside Shopping Centre in Victoria. "A substantial amount of upgrading was required for this section of the mall," says Guldin. "A roof recover was not possible in this case, so we went right down to the suspended concrete deck and applied a new conventional roof system consisting of an integrated air/vapour barrier, rigid insulation and slope package to improve thermal performance and drainage, and finished with a two-ply modified bitumen [torch-on] roof membrane. The layers of this roof system further enhance thermal performance. "For this particular project, the designed roof system was governed by the existing structural deck. You need to select a system that is most appropriate for the deck, and it has to be well designed in order to optimize water resistance. Again, consultation is key." Another type of project in which RJC is becoming more heavily involved is plazas and podiums that protect below-grade parkades, as well as controlled commercial and residential spaces. "We design waterproofing systems on these surfaces to protect the structure in addition to providing the environmental separation and enclosure performance the protected space requires," says Guldin. "One of the primary challenges in designing a system like this has been the transition of the waterproofing system/membrane to the exterior building enclosure, or the exterior wall. The waterproofing typically won't have any problems in the field, it's the tricky areas at transitions, interfaces, termina- tions, and penetrations that need some thought and effective design." Guldin adds that RJC is also working with the National Research Council (NRC) and the Roofing Contractors Association of B.C. (RCABC) on the prospect of recovering existing roofs (over-coating the existing roof system with a liquid applied product, or additional layers of modified bitumen roofing) instead of replacing them, in order to save money and be more environmentally respon- sible. "We're currently working on developing a prioritized set of parameters that are intended to identify roofs that would be a candidate for a recover. It would be great if a widely accepted recover standard could be developed and practiced nationally," he says. Kathy Fowler, director of marketing at Kryton International Inc., says, "We are starting to see a trend with clients using our products to support their sustainability goals, particularly the move to passive housing. There is a push in Vancouver to have all homes built to zero emissions standards in Vancouver by 2030, and one way to achieve this is to upgrade basements so they have better insulation properties. Because Kryton offers a fully integrated waterproofing system, we can help our clients achieve the best results. One of many noteworthy projects demonstrating Kryton's effectiveness is Vancouver's Jameson House, a 37-storey glass and concrete structure integrated with the 1929 Ceperley Rounsfell Building. As concrete was the main building material used throughout the structure, concrete waterproofing was a critical con- cern, and Lafarge suggested Kryton's integral crystalline technology as a solution. SEALED DELIVERED AND