There’s a few buildings we know of in Australia that, despite being designed and promoted as pinnacles of sustainability, have shown performance that has been, well, a little underwhelming.
While poor energy efficiency in sustainable buildings has often been highlighted in terms of quantitative data, a recent study by Washington State University and Carleton University in Canada collected qualitative data such as interviews to try to explain why high-performance buildings might not be so high-performing in practice.
According to the results, published in Energy Research and Social Science, much of it comes down to dissatisfaction with and misunderstanding of building automation systems.
The paper said that when occupants lost control of building features, it could lead to “unanticipated and unpredictable” behaviours.
Building automation systems have typically been installed to lessen energy-inefficient occupant behaviour, though a growing body of research suggests that overly automated buildings have led to a decreased level of tolerance for discomfort, as occupants’ “locus of control” is withdrawn.
“Many studies have shown that occupants can tolerate automated systems if override controls are provided,” the paper said.
Sadly there are many examples where such overrides are not provided.
Lighting automation was a particular bugbear highlighted.
One example was a remote weather station that had automated lights to save energy. The problem was the facility was occupied 24 hours a day, and staff needed the lights off to conduct work at night. There were, however, no light switches.
“We found out the employees would have to sit still for about 15 minutes for the lights to go out,” Washington State University assistant professor Julia Day said.
“In one instance, after sitting still for 15 minutes, an employee sneezed, turning the lights back on, and the employees had to then start over the process and stay still again.”
Some occupants have implemented their own work-arounds to get control back. One example saw an occupant apply tape to motion sensors because the lights gave them a headache. Another resorted to using a drinking bird toy to keep lights on because the motion sensor was located around a corner and the lights kept going off.
Ventilation was another area where occupants were confused by or not correctly using systems.
For example, one building had included a signalling system to let occupants know when the best time to open up or close the building was. However, most staff didn’t even know what the signals meant.
“I have seen people taping motion sensor light switches to keep their lights off, people placing popsicles on thermostats to turn on the heat, and even someone taping a quarter onto a window sill to reflect light onto a thermostat to turn on the AC,” Dr Day said.
“People can get pretty creative, but why not design it so they can use it in the first place? We need to create environments where people can be productive.”
From the interviews, five dominant themes emerged regarding building underperformance:
- Social influences: stories about occupants not wanting to affect others and/or the culture in the building not being conducive for individuals to improve indoor environmental conditions (for example inflexible dress codes)
- Economic concerns: stories where occupant behaviour is linked to whether they pay for energy or water, and when they justify behaviours based on costs
- Misalignment of occupants and designer/operator: stories where occupants behave in ways that while entirely logical and intuitive to them, greatly contrast design or operational intent
- Lack of control: stories where occupants have a lack of control or perceived control over building systems
- Pure discomfort: stories where occupants complain about local or global discomfort in a building
Dr Day believes gathering more qualitative information on building use can help to reduce occupant errors and inefficient work-arounds seen in high-performance buildings, and help designers create buildings that are more intuitive to users.
“We were learning more about occupant behaviour through open-ended answers in the surveys, versus just looking at the numbers,” Dr Day said.
“There is a lot to be learned by looking at both qualitative and quantitative data. We can learn from people’s stories and their behaviours to further reduce energy consumption.”
The research said that if energy reduction was a main goal, occupants needed access to controls where appropriate, be encouraged to display energy efficient behaviours, and helped to understand how to interact with the building to support both comfort and efficiency.
The paper recommends talking to occupants and including qualitative elements in post-occupancy evaluations (POEs); communicating POEs with the broader design community; and implementing an integrated design process that considers occupant comfort and building usability.
“It is important to save building energy use, but it is at least as important to keep the people in the building happy, satisfied and productive,” the paper says.
“A better understanding of occupant behaviours in buildings is necessary for predicting associated building performance and how to design buildings better for people.”