The University of Toronto was founded in the 19th century. What are the school’s energy management strategies for its oldest buildings?
The University of Toronto (U of T) has more than 60 buildings on its St. George campus that are more than 60 years old, 37 that are more than 100 years old, and some that are more than 150 years old. At the macro level, many of these buildings appear to be energy-efficient but their efficiency often comes at the expense of their occupants. Most of these buildings do not have central ventilation or air conditioning but all have operable windows. Many have “window shakers” or localized air conditioning rooftop units for specific areas. This means they’re reasonably efficient in terms of energy use but they’re not cutting-edge work environments. Two things automatically hinder their retrofitting potential: the sheer cost of adding a central air conditioning and ventilation system within an existing structure, and the challenge of finding the space required to install shafts in the building.
Very old buildings are, in one sense, very efficient due to the thermal mass provided by their thick walls. Surprisingly, a number of U of T’s old buildings are simultaneously inefficient when it comes to thermal use. This is because their steam-heated radiators cannot be easily controlled. The heat is either on or off and, therefore, it’s not uncommon to see open office windows in winter. Retrofitting these buildings can be prohibitively expensive, particularly if they contain asbestos. Replacing steam-heated radiators not only requires new mechanical equipment but also entails replacing all piping and radiators in all areas of the building. This work cannot be done in winter and is optimally done when the building is empty, which means that swing space (rental space) may be required. Heritage considerations are another significant challenge.
The best energy reduction strategies in very old buildings are the basic cost-effective ones such as retrofitting the lighting and ensuring the original (and often leaky) windows are caulked to prevent heat loss. Window and door weather stripping can also provide savings.
U of T also has a ‘cool roof standard.’ This involves replacing roofs that have no insulation with roofs that have an R-26 insulation value and a reflective topping that reduces heat gain in summer.
Within buildings, there may be gains to be made on the often overlooked side of the efficiency equation: the effective use of space.
Ron Swail is assistant vice-president of facilities and services at the University of Toronto.
