Sustainable Design a Key Component of DUKE Condos / by stephanie calvet

(this is an interview I gave and article I wrote for UrbanToronto) Stephanie Calvet sat down with Michelle Xuereb, architect and sustainability strategist at Quadrangle Architects, to discuss the green aspects of DUKE Condo’s design. The mid-rise building, which takes its name from an amalgam of Dundas and Keele streets in The Junction, is under development by TAS.


TAS has been trumpeting the lengths they are going to, to create a sustainable condominium building in Toronto's Junction neighbourhood since launching DUKE Condos last year. It is encouraging to see a developer raise the bar beyond what the building requirements call for.

For TAS, it is about building community, about being a good neighbour, and understanding there is a social, economic, cultural and ecological side to everything. TAS is motivated to build their business philosophy, outlined in their ‘Four Pillars of Sustainability’, into all of their projects.

Was the decision at DUKE to ‘go green’ to the degree that it is in anticipation of new energy efficiency regulations in the building code?

For this site, they have to comply with City of Toronto Tier 1 and the Green Roof Bylaw. Anything above that is their own initiative.

High window-to-wall ratios are a current condominium design practice in Toronto, a feature that seems market-driven, not rooted in energy performance. How do we reconcile that with the fact that significant energy savings are available in building envelopes with less glazing?

I think it is actually more developer driven, and also driven by economics. Putting up a window wall system is straightforward and quick – it makes everything happen faster. Sales took off on this building and it is not floor-to-ceiling glass. I believe you have to put something out there so people realize they want it. DUKE has a specific character and people are attracted to that – and the scale is right, the materiality feels good, and it is just standard materials: windows, brick, and some metal siding. It is quite simple but it is a different approach than just cladding in glass.

Which aspect of the building’s design do you think has the biggest impact in terms of sustainability? Through which methods did you assess net energy savings?

The envelope is key. It’s about getting window-to-wall ratio down— 40-50% is where you want to be—using the best glazing possible, and reducing thermal bridging as much as possible. The window will always be the weakest link in the building so the more you can shrink that aperture, the less heat you’re losing. At DUKE we’re using aluminum frames and the glazing is argon filled with a low-e coating. At Quadrangle, we design what we think is the right thing to do and we have to be asked to do less. We feel we have to lead that way. The bonus from the recent Toronto Green Standard changes is that it makes it a level playing field for all developers – everyone has to do this. We do energy modelling early in the process.


There’s great citywide interest in local and organic food. DUKE’s south side terraces are being lined with built-in planters that can be used for home gardening. Are you ‘leading the way’ by incorporating this feature into the design or is it in response to social shifts and increased demand for urban agriculture in residential developments?

There are various non-profit organizations out there advocating food policy in buildings, trying to push legislation, trying to speak to developers about how to make food happen. We too are working with these companies to help promote and push these initiatives – for one, we put food production ideas in our renderings. There’s no reason your front garden can’t have edible food. And TAS has been doing it from their side as well. We are all hoping that it really takes off. And the planters came out of another reason as well: affording neighbours to the south some privacy by having the depth of this green buffer, rather than just a railing. When there are multiple reasons why an element makes sense, it’s likely to stay ingrained in the building, and not get value engineered out.

Standard suites include engineered hardwood flooring, water-conserving fixtures, energy efficient appliances, programmable thermostats, and Energy Recovery Ventilators (ERV) to reduce energy demands and enhance air quality. Have these innovations come down in price so that the developer can provide them as part of the standard offerings?

There are a lot of things that have become more standard, like low-VOC flooring or paint, and it has become a requirement to provide energy metering to each suite. ERVs haven’t really come down in cost – the additional ductwork costs everybody more – but TAS has elected to do this anyway because it’s about improving indoor air quality and it’s something they can market.

A total of 25% of the parking stalls will be equipped with an electrical outlet for plug-in and provisions were made for future energizing of the other spaces. Will you provide a central bank of dedicated charging stations? What does that mean for the electrical capacity of the building for each space to have the possibility of EV chargers? Why go this route instead of the (less costly) car-share option?

This is a goal of TAS’ to do this. At one point we had a car share vehicle space within the building but there’s enough within the neighbourhood. The way things are going in the future, it will become more and more economical to have a plug-in electric vehicle. People in North America are pretty attached to their individual car ownership. To provide infrastructure for people to have plug-in electric is about future-proofing the building. But as for how it’s specifically going to work at DUKE, whether they will run it to a panel that is individually metered, we haven’t finalized it yet.


As per the city’s Green Roof Bylaw, certain % coverage of the roof is required to be a green roof, based on the building’s gross floor area. Which system will you provide at DUKE?

It will be a drought-resistant, low-profile, extensive green roof (vs intensive – where you can plant trees and shrubs). Probably a tray system. Green roofs raise your top of roof that much higher, so you have to be careful of how you distribute the heights because you lose potential area if the roof is too thick, plus you have to consider structure. There is always a trade-off.

The benefits of a green roof are multifold. Do you believe that in the near future, sky-gardens will become both desirable and inevitable as part of a growing cityscape?

I wish it would become more prevalent because we see it as a positive attribute. Right now, green roofs cost more money and the market isn’t necessarily looking for it, so we’re not there yet. And the Bylaw % requirements aren’t high enough in terms of how much you are obligated to provide for anything more than something quite basic, i.e. a low-profile extensive roof. If the developer wants to build a lot more, it’s just additional expense and if they can’t use it as a marketing tool, chances are they won’t opt to go that route.

How do you think we can best encourage that sustainable strategies be followed on all building projects, from conception through construction to furnishing?

There have to be financial incentives and legislation, otherwise it won’t happen, as well as the fact the City of Toronto itself has taken a leadership position on this: 15% better than the current building code. That level is really the 2017 version of the code. It’s those sorts of energy initiatives – being a certain percentage better than code – that have been happening at the municipal and the provincial level, which have been pushing the envelope.

There is always cost involved with change, i.e. change from traditional to sustainable construction practices. Consumer awareness about conservation and low impact development issues is key and people might be interested in ‘doing the right thing’, but when the rubber meets the road, they aren’t always willing to pay more. What could be the facilitating mechanism that will encourage consumers to make the extra effort for eco-friendly avenues knowing that payback will come later?

I’d say it’s the consumer, the purchaser. At the end of the day, it’s the cost per square foot, and they want to know they are getting a certain kind of countertop. Right now, what I’m hearing from marketing folk is that people don’t want to pay for ‘green’ initiatives, they think that the buildings should come with them. The green is just part of the story that people are expecting to see as opposed to it being an add-on, and having to pay more for it. To me what would be interesting would be a developer who would work really hard to bring those numbers (maintenance fees) down and the way to do that would be to provide an extremely durable building.  

Stephanie Calvet is an architect and architectural writer based in Toronto. She can be found at