Making building performance a selling point, and moving on from the glass tower
By Richard Witt, Executive Principal, Quadrangle & Michelle Xuereb, Director of Innovation, Quadrangle
Sustainable building design is not a new concept. With the development and implementation of LEED in the early 1990s, sustainability became mainstream but has struggled to effect real change in the way we think about building performance, requirements or aesthetics. Economics and sustainable building design are at odds – sustainability is an extra cost, weighed against budget and relative value.
The Council of Tall Buildings and Urban Habitat concluded in their study Downtown High-Rise vs. Suburban Low-Rise Building that recently completed buildings significantly underperform in comparison to their counterparts from 50 years ago. The days of the glass skyscraper are coming to an end. Passive systems direct the way forward, as opposed to compensating for inefficiency with active systems.
Buildings are the key contributor and solution to climate change mitigation and adaptation.
According to the latest inventory release (2017) by The City of Toronto, 52% of GHG emissions in Toronto come from buildings, predominantly from burning natural gas to heat indoor spaces and water. Consequently, buildings must also be a climate change solution. The City of Toronto recognizes this in its Zero Emissions Building Framework, which is why the Toronto Green Standard (TGS) has us on a path to net zero buildings by 2030. What about the code? There is a plan to move Toronto to net zero by 2030, but it is not clear, given the current political climate, whether this proposal will be executed. Passive design solutions increase durability and climate change resilience while lowering energy usage, embodied energy from maintenance, and GHG emissions.
Passive solutions allow us to both mitigate and adapt to changing weather.
Based on the Climate Driver Study completed for the City of Toronto, we know that days are getting hotter, there are more of them and there are more of them strung together in heat waves. We are also experiencing larger storms, with heavier amounts of precipitation falling at once. The main issue we will have with our buildings is overheating and flash flooding – both in combination with power outages. This again reinforces the need for passive design solutions.
These power outages generally happen on our hottest and coldest days as a result of people cranking their AC or heating. The higher the total effective R-value of the building, the better they are able to maintain the indoor air temperature in the case of extreme temperatures without power.
The City of Toronto recommends that people be able to function independently for a minimum of 72 hours without power. In a residential building, maintaining indoor temperature is key to allowing people to shelter in place within their homes.
• At a basic level, a building is meant to shelter people from the weather – to keep people warm when it’s cold and cool when it’s hot. Glass is a very poor insulator, leaving residents feeling physically uncomfortable and paying high energy bills.
• As architects, the best thing you can do is reduce the amount of glass and increase the amount of well-insulated walls. We understand that keeping windows to about 40% of the wall area is the single most effective way to reduce the energy footprint of a building. Real walls with windows may seem old fashioned, but they don’t need to be. Our focus is on creating a thoughtful, well-designed building with an aesthetic that lends itself to real walls and windows.
• Unlike glass, insulation slows down the movement of heat. This allows you to hold onto heat during winter, making people more comfortable and more likely to actually use the spaces at the perimeter of their unit.
