If you were to enter the building in the following picture, would you use the revolving doors?
Most people would select the swinging doors on the sides.
People who use swinging doors increase their carbon imprint. Doors that swing open let heat, cold and wind into a building while revolving doors block outside air. According to one study, 8 times more air is exchanged by swinging doors than those that revolve. Because swinging doors increase the need for heat and AC, they add to carbon emissions.
Concerned that most people avoided revolving doors, several MIT students decided to observe and analyze door use on campus. They had 3 basic questions:
- Can habits be reversed?
- What effectively changes habits?
- Can having people change one habit have a large impact on the environment?
Researching their study, they proceeded to figure out the waste, to quantify revolving door use, and then to try to encourage new habits. The waste is summarized in the following chart. As for the use, predictably, most people used swinging doors. Then, to change people’s habits, they experimented with different kinds of signs (below) and observed the impact of architectural designs. The implications of their results were far reaching. By increasing seemingly small “green habits” like using revolving doors, they could make a global difference.
As for the economics, you can see it is mostly about cost. Defined as sacrifice, the cost to use a revolving door can be high. Revolving doors require more time and effort and they frighten some people. Behavioral economists might add that avoiding them is a social norm and easily accessible swinging doors are the “default.”
Finally, a bit of history:
Folklore has it that the inventor, Theophilus Van Kannel, created his revolving door design to avoid holding doors for women. The patent he received in 1888 was for a “storm-door structure” that was noiseless, had weather strips, prevented “the entrance of wind, snow, rain or dust,” and reduced the possibility of collision” because it moved only in one direction.
Sources and resources: H/T to 99% Invisible for alerting me to the sustainability significance of revolving doors and its link to the MIT paper, “Modifying Habits Towards Sustainability: A Study of Revolving Door Usage on the MIT Campus.”