By Annemarie Reimer

Stratford’s Dufferin Arena may look like other buildings in the city, but a closer look reveals a green scrim along the roof edges. This green roof is one of the many energy efficient features in the state of the art arena, completely renovated in 2010.

Jim Bryson, Community Facilities Manager, was in charge of the project. He describes the original outdoor ice rink building as having numerous issues, from low building standards to nightmare energy consumption. That rink was enclosed and renovated over the years until federal funding through a rink program matched $2 million contributed by the city and resulted in a totally accessible modern arena which uses half the energy of Stratford’s William Allman Arena.

The low maintenance green roof will provide insulation for up to 40 years, about 3 times longer than an ordinary flat roof. It consists of sedum planted in 4 inches of dirt on top of a membrane. Sedum is able to survive a 4 month drought if needed. A rain capturing system waters the sedum and, through an underground cistern, also provides irrigation for the nearby community garden.

In addition to the energy saved by the green roof, there are several other significant energy conservation features of the arena.

Notes Bryson, “The heat we take out in the ice-making process we actually put back into the floors to heat the dressing rooms.” This was very innovative at the time.

Another feature is the ice battery which circulates glycol outside to refrigerate it instead of using energy to do so. In the beginning, this system worked too well and the dressing rooms were too cold. Adjustments in the third year had to be made.

The walls inside the Dufferin Arena are very effectively insulated to a high construction standard. With a slight chuckle hinting of pride, Bryson reports, “When we go to take the ice out in the spring, it takes almost a week for us to get it out, because it’s so cold inside there.”

The low maintenance green roof will provide insulation for up to 40 years, about 3 times longer than an ordinary flat roof. It consists of sedum planted in 4 inches of dirt on top of a membrane. Sedum is able to survive a 4 month drought if needed.

For the building’s state of the art energy efficient design, RETscreen, an energy conservation program invented by the National Resource Council, was used. It provides specific accurate information on the actual heat radiation at any given height and location by using real time data from NASA on the specific location of the project. This kind of input informs insulation decisions, such as whether 8 inches will be used instead of 4.

The arena also has a snow pit inside to avoid the energy loss and increased humidity typically caused when ice shavings are dumped outside after resurfacing. At a busy arena, the ice is resurfaced often in a day. The snow pit allows for the snow to be melted without opening the outside doors and letting heat in or out. Dufferin Arena’s snow pit results in a 40% reduction of energy costs. Refrigeration power costs are reduced significantly. Also, the melted ice which contains a coolant, is not released outdoors into the environment but is processed via a sanitary sewer system inside the building.

Another renovation that made the arena unique at the time was the polymer glass installed to allow natural light in, thus making indoor lighting mostly unnecessary during daytime hours.

The  Dufferin arena renovation is an impressive example of energy conservation. The energy costs of the original building were reduced by half even though the size was increased by 10,000 square feet. The arena uses mostly electric power, which is non-fossil fuel energy since Ontario’s last coal plant closed in 2014, but the energy efficiencies also minimize the use of natural gas in the dehumidification system and in heating the dressing rooms.

“We certainly took that building and took it a long way,” Bryson concludes.

Energy conservation is ongoing for Bryson in his role as Community Facilities Manager. This month, the Rotary Complex completed the replacement of all the lights in the parking lot with efficient LED lighting, reducing energy costs by two thirds. Bryson anticipates that the planned community hub for downtown Stratford will likely be the next big focus of energy conservation.