For the OAA Headquarters, located at 111 Moatfield Drive in Toronto, the glazing is a key component of achieving the zero net carbon retrofit goal. Windows can be responsible for up to 40 per cent of the total heating, cooling and lighting energy consumption. By undertaking an envelope upgrade and installing View’s Dynamic Glass product, the windows will improve the building's energy efficiency. Compared to traditional low-emissivity (low-e) glazing, the glass is expected to reduce the building’s peak load by about 23 per cent!
The OAA Headquarters is often thought of as a glass box. However, only the southeast corner (with the entrance) is curtain wall. The east and west facades have 40:60 window-to-wall ratios, and the north has very few openings. This is actually a very good example of 'spending windows wisely.' East and west facades are prone to overheating in the summer, as is the case with this building.
Access to views and daylight is also important and has been shown to positively impact productivity and well-being
. At the OAA Headquarters, views of the Don River GreenBelt system (to the north, east and south) provide a natural vista.
Southeast view in summer.
South view from the second floor in winter.
South view in the spring.
Stairwell view in autumn.
The OAA Headquarters’ unique site is an asset to members, employees and volunteers who use and visit the building. Finding ways to maintain the views and address energy efficiency is critical—now and into the future. The importance of unobstructed, natural views has been cited as increasingly advantageous. A recent study
indicates that the importance of light and views may be directly linked to the need for a break from electronic devices: “the longer [people] use their technology devices, the more they desire a visual break such as taking a walk or looking through unobstructed windows to an outside view.” Therefore, the need for finding ways to address energy efficiency while maintaining glazing becomes increasingly important to users’ well-being.
The new dynamic glass will improve the performance of the building by blocking unwanted heat and optimizing for daylight and glare. These smart windows have the ability to change traditionally static performance characteristics such as visible light transmittance (VLT) and solar heat gain co-efficient (SHGC). The proprietary glazing also reduces overall HVAC energy consumption and costs by limiting unwanted heat gain in summer, but still allowing beneficial passive heat gain in winter. (For more information, click here
Each window is addressable by a control system that uses a combination of sensors, predictive comfort issues based on solar paths and weather reports to eliminate glare and excess heat. The glazing changes its tint level so slowly that it is almost unnoticeable to occupants. Additionally, occupants can control the windows closest to their desks if they want their view to be blocked or made more clear.
The OAA has replaced existing glazing on the second and third floors, with work continuing through December. The curtain wall itself was replaced six years ago with a Mylar-based triple pane to increase the energy efficiency without increasing the weight.