University of Calgary

Growth 
Industry

Submitted by alumni on Wed, 05/13/2015 - 19:20.

Growth 
Industry

Get ready to see weed-whackers on rooftops — the season for green roofs is just warming up
by Deb Cummings

Kerry Ross on the green roof atop Earth Sciences

Today, all you’re likely to find on the roof of the Earth Sciences building are two 600-sq.-ft. patches of crispy brown sedums and 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 Msc 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 stormwater runoff;
  • Air quality improves which 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 that green roofs have on stormwater management and urban climates. The 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 parametres 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. U