Graeme Stewart is a principal of ERA Architects which was the lead architect of the Ken Soble Tower transformation, one of the largest EnerPHit-certified projects in the world. www.eraarch.ca
1. How did ERA Architects become involved in the Ken Soble Tower project?
ERA Architects had been working for over a decade on the Tower Renewal Project, a strategy for the revitalization of Canada’s aging postwar apartment neighbourhoods, through which we gained experience on tower retrofits. As part of the Hamilton City Housing portfolio of buildings, the Ken Soble Tower was in a distressed, abandoned condition. Based on our experience, we were brought in to do an assessment of what to do: tear it down or retrofit.
2. Deciding to do an EnerPHit transformation was a bold decision. How did you arrive there?
I am pleased to say that the decision was largely made for us by Hamilton City Housing CEO Tom Hunter. He came from the health care sector and said that we build world-class hospitals and need to do the same for our public housing. He understood the long-term benefits of doing an EnerPHit transformation, and the project moved ahead from there.
3. Once the project was a go, how did the process work of coordinating the various disciplines in the team?
When Hamilton City Housing decided on pursuing EnerPHit the intent from the start was to achieve certification. This kept everyone ‘honest’. It was crucial to have a fully co-ordinated team which we assembled based on our experience. The team included: Entuitive, JVM Consulting, Transsolar, Reinbold Engineers and the certifier from PHI in Germany among others. At every step – during design development, review of assemblies, costing reviews – the team always asked if we were meeting PHPP targets. We then worked with PCL on construction mock-ups that would meet the criteria of EnerPHit and serve as the standard should alternate details or products be suggested by the trades. Through this process we arrived at a tight ‘specs package’ such that the project met performance and was ultimately certified.
4. What did you learn from this first project about what worked and what could be improved?
As far as we know, this is the largest residential EnerPHit project in the world. The precedents for this type of work come from Europe but we realized that we need solutions that meet North American practices, products and trade familiarity. Our design made this its focus. The construction manager PCL was critical in the strength of their quality control regime, but some trades wondered early on if the PassiveHouse was overkill. Yet as testing procedures became easier the consensus was these were key practices for use in future projects, Passive House or overwise.
There are two other observations. We would love to have trades more familiar with high-performance retrofits, and a supply chain that can provide more of the types of products for this type of work. But the evolution will happen. Since we went to tender three years ago, many more suitable products have become available.
5. Is the Ken Soble Tower transformation a practical template for the many similar towers in our building stock?
A resounding yes. The project gave us a lot of elbow room to try things because it was empty. We can apply the lessons learned to an occupied building. It was cheaper by half to renovate the Ken Soble Tower rather than tear it down and replace. The economics will improve further as the supply chain and trade skills improve. The incentive is an improved quality of life in revitalised buildings that are quiet, more comfortable, and more economic to operate in the long term.