Issue link: http://digital.canadawide.com/i/1295215
E X P E R T I N S I G H T E N G I N E E R E D A S S E M B L I E S Façade Industry' (June2020/Construction Canada) we see measures that are seldom included in warranty requirements but undeniably increase the success of a material and/or system. Examples of this are comprehensive shop drawings and more substantial deflection limits (L/300). These measures are a perfect example of what we are driving at here. They are not included in warranty requirements, so sel- dom will they be considered in detailing and installation, yet they will most certainly impact the lifespan of the product. As suggested previously, we want the warranty, but we really want the success of the product and the lifespan that's expected – or better than expected. How do we get there? What should we know and where should we be looking? There are many great resources for addressing best practices in façade installation. For example, one well recognized resource is the Engineered Assemblies system2 design guide. This is a comprehensive and holistic guide that covers the broad and finer strokes of detailing and installing lightweight façade systems. Its guidelines relate to a plethora of materials and products throughout the North America façade market. One of the key issues it addresses is the effects of climate change on façades that are always on the front lines of the weather battlefield. Considering the threat of climate change and the impositions it makes on façades, subjects such as coefficient of expansion and contraction should be taken very seriously. In Ontario and throughout many parts of Canada we see severe deltas in temperature over the course of 24 hours, whether it be over the freeze thaw line or not. This dynamism mixed with precipitation, often found throughout the Maritimes, is a mighty adversary when not designed for. In the seven fundamental design principles outlined in the EA/DG2 (Engineered Assemblies design guide), there are elements that certainly determine the success of a façade material, or at the very least thwart unnecessary stress. Another example would be respect for traditional points of deflection in a concrete and steel superstructure, or ensuring the implementation of a high-performance active plenum to moderate thermal variations and stress. No material ever benefits from stress, and whenever stress can be avoided, it should be. This will certainly prolong the lifespan of any material. THREE: What does warranty tell us about the lifespan of a product? Let's look at how many product warranties are designed. Warranties are typically an insurance policy. Here's an example: A company manufactures a product and based on variables that may include some or all of the following: • The cost of the product • The record of success • The cost of replacement • The expected success during the suggested warranty period. Some value in the form of compensation is attributed to some components deemed a 'failure', as defined by the manufacturer, and offered to the purchaser. Sometimes the warranty is transferable to new owners through sale, sometimes not. We may also see some initial support by the manufacturer for a warranty that does not reflect the quality of the product whatsoever, simply to earn the product some market recognition and share. Alternately we may also see a warranty that is rather short and seemingly insignificant that doesn't reflect the product's remarkable structural integrity, resilience, and general quality. A warranty is an insurance policy and is meant to behave that way. Like any insurance policy, seldom is it a 100 percent complete and accurate reflec- tion of all the facts surrounding what it represents. The cost of the policy is determined by the insurance company offering it, is based on the risk of fail- ure versus success, and is passed on to the manufacturer (the manufacturer in this case is providing the warranty). The manufacturer divides the cost of the warranty across the products it pertains to ($/sf for eg) and the resulting figure is added to the selling cost of the product. Done. So the warranty is based on vectors that are completely separate from the innate quality and lifespan of a material and/or system. It's a short-term objective and, one could argue, completely at odds with the long-term objective that is our construction project. CSA S478-2019 Durability in buildings works hand-in-hand with lifespan. TCSA S478-2019 is a perfect example of some of the measures we should be focusing on. It is the second edition of CSA S478, Durability in Buildings and supersedes the first edition, published in 1995 under the title Guideline on Durability in Buildings. The first edition of CSA S478 was issued as a 'guidance docu- ment' only. This second edition has been developed as a standard that can be referenced in the National Building Code of Canada (NBC). This is something that has been addressed in recent months through insti- tutes such as Façade Tectonics. The standard lists minimum requirements to assist architects and engineers in developing durable buildings, as well as providing a framework addressing the expected service life of a building or various building elements. Annexes to the Standard provide general guidance on environmental and other design factors that have an impact on the durability of a build- ing, a building material, and/or a building component. This Standard was prepared by the CSA technical committee on designing for durability, under the jurisdiction of the Construction and Civil Infrastructure Strategic Steering Committee, and was formally approved by the Technical Committee. It was also developed in compliance with Standards Council of Canada requirements for National Standards of Canada and has been published as a National Standard of Canada by CSA Group. This is a funda- mentally significant move in steering the market towards success and the subject of lifespan. IN CONCLUSION We have the science, the ability, and a multitude of specific regional best practices to employ towards bettering the lifespan of our facades and com- plete buildings in general. Selecting products to accomplish this can be a comprehensive task and, will likely involve a holistic approach, encompass- ing material handling, detailing, storage, and installation. Warranty is an important component for the aforementioned reasons, but lifespan is not determined by the design or provisions of a warranty. Uniting the experience and skill of the house of design and the field of construc- tion, along with quality materials and a success driven design/installation mindset, will certainly yield the best outcome of performance and lifespan we can hope to gain. ■