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+ University of Alberta Donadeo Innovation Centre for Engineering building featuring Ductal precast concrete bands from Lafarge. A PR IL 2016 | 13 Precast Concrete PHOTOGRAPHY COURTESY LAFARGE CANADA INC. T The interplay of technology, fashion and esthetics has been helping to dramatically expand the palette – and the visual impact – of precast concrete building enve- lopes and cladding systems. "Its excellent versatility allows for finishes from one end of the spectrum to the other. Its plasticity provides depth and geometric shapes that create eye-catching facades," says Brian Hall, managing director with the Canadian Precast Prestressed Concrete Institute (CPCI). As owners and developers compete for buyers and tenants, designers look to add visual interest and depth to facades. "In many cases, designers are turning to precast concrete to meet these needs. Besides being a high-performance building material and system, pre- cast concrete is available in practically any colour, form and texture. It can be veneered with other traditional building materials such as brick, granite, limestone, ter- racotta, tile and more. This provides the look and feel of other materials while adding all the benefits of a precast modular panelling system," Hall says. Also, he notes, various finishes can be combined in a single panel. This provides an efficient way to deploy a multitude of facade treatments with less costs and detailing time. Given the perennial appeal of brick, it is no surprise that thin brick-faced concrete panels are being increas- ingly used. Afterall, they combine the esthetic charm of other materials with structural advantages of architec- tural precast. Brick facings can cover the entire panel or can be used to create strategically-placed accents. "Complex and intricate details such as arches, radii and corbels with various bonding patterns can be incorpo- rated into finished precast panels," Hall says. Self-supporting precast panels that are easily attached to the structure eliminate the need for struc- tural steel lintels, metal studs and/or a block back-up that is needed to support field-set brick veneer. The precast panels provide the exterior air barrier with- out additional rainscreen systems. Hall notes that more information on thin brick providers can be found on the Thames Valley Brick & Tile, Endicott, Metro Brick, Summitville and Roben Tonbaustoffe websites, all of which highlight ideas on design and application opportunities. A soon-to-be released Total Cost of Ownership study, independently completed by Hanscomb, will show that the real capital cost competition between six storey or lower wood and total precast concrete structures favours total precast concrete, Hall says. "The study will disclose longer than expected con- struction timelines, lower modularity factors, addi- tional financing costs, additional insurance costs and higher operational costs for wood structures. In addi- tion to lower overall durability, higher lifecycle costs, higher health and social costs lead to a higher overall total cost of ownership for wood buildings. The study highlights that wood construction is not an ideal solu- tion except for those who only consider upfront capi- tal costs, which can be largely offset by the total cost of ownership elements," Hall adds. Combining the plasticity potential of freshly-placed concrete with today's 3D form liner and photo-engrav- ing technologies is opening up an almost infinite range of design options. The use of elastomeric polyurethane form liners for patterning and texturing concrete sur- faces can produce complex and detailed designs, patterns or images on exterior concrete. Supported by a modern photo-engraving technique, photographic images can be transferred onto a concrete surface, with the pattern varying from coarse to fine, depending on the image used. Shaping Up Precast concrete is being used in highly innovative ways by GODFREY BUDD

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