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Innovative research germinating on UCalgary green roof

Researchers ponder the future of large-scale living roof systems


MA student Kerry Ross, a lead coordinator in UCalgary’s Green Roof initiative, is studying what impact green roofs have on storm water management and urban climates.

May 13, 2015

Today, all you’re likely to find on the roof of Earth Sciences are two 600 sq. ft. patches of crispy-brown sedums, perennial leftovers from last summer, but the season for green roofs is just warming up.

It was on this flat roof where we recently found Kerry Ross, a lead coordinator in UCalgary’s Green Roof initiative who is taking her MA in geography with an energy and environment specialization. Stooping down, she examines the resilient little succulents that have survived the winter, existing on a thin layer of growing medium with low organic content, growing in a little square plastic module. One of the first accredited green roof professionals in Canada, and a key player behind the green roof at City Hall as well as another at the University Research Park, Ross explains why we should welcome the day when weed-whackers do appear on our rooftops:

  • As vegetated cover, green roofs eat CO2 and produce oxygen, cleaning the air.
  • Biodiverse roofs, whether they are homes to herb gardens, aviaries or goats, act as natural insulators and save energy through significant summer cooling benefits and provide some winter heating reduction, particularly for older buildings.
  • They reduce quantity and improve quality of storm water run-off.
  • They also improve air quality that translates to savings in the form of reduced health-care costs and emergency room visits.
  • Green roofs last twice as long as conventional ones.
  • They also decrease noise levels by up to 50 decibels.
  • And, they enable urbanites to experience nature.

Under Geography professor Geoff Hay, Ross and several other graduate students are contributing research to the Tri-City NSERC Strategic Project that’s investigating the impact green roofs have on storm water management and urban climates. Earth Science’s rooftop garden is wired with all sorts of instrumentation to provide information on temperature, humidity, wind speed and direction, sunlight and other parameters accessible online from roof data loggers.

The other university team members — from the U of T, Western and St. Mary’s — have planted exactly the same plants and are looking to better understand the type of vegetation best suited to our climate. The galvanizing question is: what would be the long-term environmental effects if we were to expand a green-roof strategy to an entire campus or a city? Other projects in the works include the installation of a green roof living lab on the new engineering building and on Calgary’s Municipal Building.

As for now, Ross is taking it one roof at a time, dreaming of green-roof domination.