While there are the three pillars of sustainable development--economic, social, and environmental--the first that I tend to think of and focus on when it comes to building development is the environmental. When measuring the environmental sustainability of a building, we should consider the impacts from the entire life-cycle, including construction, use, and end-of-life.
To be considered sustainable, there should be minimal environmental impact in every part of the life-cycle. For construction, that can include the types of materials and how they are sourced, and the construction methods (energy/water usage, waste, emissions, etc.). In the use-phase, that’s where we look more into the energy efficiency of the building, passive heating/cooling, waste/recycling, water usage, and more. The phase that’s probably often overlooked is end-of-life. Can the building be upcycled for another use after its primary one? If/when demolished, how recyclable are the parts?
Ideally, a sustainable building should be self-sufficient in its use phase, i.e. by getting its energy from solar, implementing water catchments and recycling, etc. This way, the building would have minimal negative impact on the natural environment with minimal/non-existent GHG and pollutant emissions and waste.
There is a lot of inspiration that can be taken from the Living Building Challenge, which has ambitious standards relating to environmental sustainability, but also focuses on human wellness/social sustainability. From Living Buildings, we find that not only can we reach net-zero, but net-positive is possible. Take, for example, the Bullitt Center in Seattle, which saw net-positive energy generation from their solar panels in the first year. This may be surprising considering that Seattle is notorious for limited sunshine.
Another example of a certified Living Building is the VanDusen Botanical Garden Visitors Center. While the Bullitt Center is impressive, something I like about the VanDusen building is that it doesn’t compromise on the architecturally interesting design.