— Feature —

Real change – building a sustainable city

It is the height of the day in the downtown core, but you wouldn’t know it. The streets are bare except for the odd person, wrapping whatever they can around their face to try and filter out the yellow haze filling the space between the darkened buildings. The sun casts a sick glow on anything it touches as health experts advise people to stay indoors.

This isn’t the trailer for a new science fiction dystopia film – this was Edmonton twice in the last year as smoke from forest fires elsewhere blew over the city.

Heavy smoke and heat waves are two weather phenomena experts are trying to re-align the city to face as climate change progresses.

“Forestry experts tell us the forests are drying from climate change,” said Alberta Capital Airshed executive director Gary Redmond. “They anticipate a lot more burning. So I think we can expect more smoke in the air than we’re used to.”

Redmond emphasized smoke isn’t the only significant air pollution problem facing Edmonton. Cold air in the wintertime can keep pollution closer to the ground and lead to air quality warnings, though ash and carbon particles from forest fires are several orders of magnitude worse.

A non-profit air quality monitoring group, part of the Airshed’s work is to bring stakeholders together to identify potential problems and brainstorm solutions.

Redmond advises people in good health to keep physical activity indoors during smoky days, where the Air Quality Index is at least seven. People with health issues should take precautions if it’s as low as three. Covering your face with a scarf may actually do more harm than good, because it pulls particulate matter in your airway. 

One solution Redmond advocates is Community Clean Air Shelters, retrofitting public spaces with air filtration systems to give people safe places to breathe, which have been effective at improving people’s health.

Working from the other end is Shafraaz Kaba, principal architect of Ask for a Better World and Energy Efficiency Alberta board director. Kaba has ambitious ideas for dealing with air quality and other problems facing the Edmonton downtown.

“Why don’t we build in air filtration in homes?” he asks while looking gloomily out at yet another stormy day in Edmonton. “Or ways to mitigate the effects of massive amounts of rain?”

Preparing for a hotter downtown

Kaba is keenly aware of the challenges Edmonton is facing. As part of the Energy Transition Advisory Committee, he helped develop the “Climate Resilient Edmonton: Adaptation Strategy and Action Plan,” an examination of environmental, health and economic issues and strategies. It was presented to city council in November 2018.

Well past arguing whether climate change is real or not, Kaba says the real questions are how is it affecting us and what are we doing about it? The solution is to both develop resiliency against Mother Nature’s wrath while simultaneously reducing the city’s carbon footprint to placate the elements.

Kaba explains this requires a more holistic way of thinking about building structures, ranging from things like the thickness and insulation of the walls, the glazing and size of windows and even simple things like the material used around them all contribute to the amount of heat a building can hold on to.

“[Forestry experts] anticipate a lot more burning. So I think we can expect more smoke in the air than we’re used to.”

Gary Redmond, Executive Director, Alberta Capital Airshed

“An example is thermal bridging, where heat transfer happens,” he says as he motions to the aluminum trimming of his 10-foot tall window. “The aluminum frame that holds the glass is a massive conductor of heat, from the inside to the outside in the winter and vice-versa in the summer.”

A more extreme example is skyscrapers, which effectively act as giant greenhouses, even in the wintertime. While not the best holders of heat, they pull enough in over a cold winter day that many commercial buildings use much of their power cooling the inside of the building in spite of below-freezing temperatures outside.

“We basically took in a global mechanical system and said ‘We’re going to do that too,’” said Kaba. “We need to design buildings that say, ‘Okay, it’s sunny and –30 C out. How do we have a mechanical system that warms cold air instead of using air conditioning?’”

Better heat efficiency not only reduces the carbon footprint of buildings, it also helps to minimize the Urban Heat Island effect – concrete and other materials like aluminum hold heat and downtown Edmonton has a lot of concrete.

This makes heat waves of particular concern. People with health complications may not be able to cool off quickly enough. This happened in Europe in 2003 where eight consecutive days of over 40 C highs killed over 50,000 people across the southern part of the continent. Sixteen years later, the United Nations now says weather events like heat waves, smoke, flooding and/or either too much or not enough rain are happening once a week on average.

“There’s a bit of a reckoning coming,” said Kaba. 

A huge variety in designs of buildings makes things even more complicated, each requiring their own solutions. Smaller buildings are better suited for solar panels because they have more surface area exposed to the sun, whereas a taller building only has one good side at best for solar generation.

“In a tall building, you have a lot more wall surface area and very little roof,” explained Kaba. “So you’re forced to consider how much of that wall you need for windows to let in daylight versus if you’re going to make them thick, insulated walls to prevent heat loss.”

Regardless of the challenges, he said the goal should be to have every building generating at least some of its power – and potentially even food – to offset the costs of building and maintaining the structure.

“It’s not if or should – it’s a must,” he said. “Every client I have, I can show them it’s a no-brainer to add solar modules to be able generate power because it’s also a risk mitigating system.

“As we decarbonize our grid, we will need any amount of electricity that’s green fed into our grid. Installing renewables now in a new building or a retrofit is far cheaper than ripping out what you put in 10 years from now to put in solar.”

“Why don’t we build in air filtration in homes?”

Gary Redmond, Executive Director, Alberta Capital Airshed

Redmond agrees pointing out that adverse health effects from excessive heat and poor air quality can have far-reaching economic implications.

“If someone works in an office building and they’re having trouble breathing, that affects the business of that building,” he said. “Air quality is going to become a business necessity.”

Kaba notes the plan to develop a central park out of four vacant parking lots downtown is a good start for offsetting both pollution and the concrete jungle heat. The next step is finding ways to establish more indoor green spaces, since winter is still going to be with us for a long time.

“Plants are a natural pollutant scrubber. The challenge in our climate is we can’t incorporate greenery into the façade of our buildings because in the winter they will freeze and die,” he said, adding that exception did not include green roofs. “You can create a green roof out of grasses and other things that survive the winter, absorb water and reduce heat.”

Another hurdle is regulatory. To pave the way for green roofs on top more efficient structures and more renewables built into them requires legal definitions, which are the purview of the provincial and federal governments.

For its part, Ottawa has been busy. Changes to the National Building Code are expected to roll out in 2020 by standardizing durability guidelines to reflect climate change trends.

Kaba maintains it makes sense for Edmonton’s downtown be ahead of the green wave and said the construction industry should lead the way.

“Buildings contribute almost a third to the energy we consume as a society and 40 per cent of our landfills are construction waste,” he said. “As an architect, I need to design something and show people how to build it without that much waste.”

“We have better ideas. Now we just have to start using them.”

There’s an app for that

Homeowners hoping to keep the smoke out will soon have a new tool at their disposal. Kaba has just finished a project with All Sky One Foundation to be officially launched in September. The Climate Resilient Virtual home will allow people to see how their home stacks up in terms of both energy efficiency and its capacity to withstand a changing climate in the Edmonton Metropolitan Region.

“We have a website that will ask what kind of environment you are in, if it’s a new or old home, and what kind of climate issues you are concerned about,” he said. “Then it will give you a model with all the things you should think about for your house in terms of structure, roofing, walls, landscape design… Everything down to making sure you anchor things in your yard, otherwise a high wind could blow it away.

“It’s giving people the tools and ideas to start thinking big picture.”