Automatic doors and revolving doors generate energy savings, improve operations, enhance user experience, and attract occupants and tenants. But if you’re considering installing one or the other to seize these benefits, making a selection doesn’t require shopping door-to-door.
Certainly not an open-and-shut case, your decision will depend on space availability, traffic flow, ADA compliance, and energy savings potential. Read on to try and close the door on this debate at your facility.
Energy Performance Spurs Retrofits
Because automatic doors open only when an incoming user triggers them, the possibility of doors being left open accidentally – a costly mistake when HVAC systems are operating – is eliminated, says Donald Moerbe, president of the American Association of Automatic Door Manufacturers (AAADM).
Even though the doors are powered, they can actually help conserve energy with tight, secure seals.
“Automatic doors are essentially used as an air lock to help manage expenses,” Moerbe explains, attributing the performance to the vestibule setup of two separate sets of doors. “There are also a variety of models available with low-energy motors.”
Revolving doors also combat air infiltration. “Energy loss depends on how many times the door is open, how large that opening is, and how long it lasts,” says Tracie Thomas, marketing manager for revolving door manufacturer Boon Edam Inc. “Because they’re always open yet always closed, revolving doors provide the least amount of infiltration possible.”
MIT researchers considered the effects of revolving doors at several of their campus locations in Modifying Habits Towards Sustainability: A Study of Revolving Door Usage on the MIT Campus.
A revolving door is only effective if it is used, however. The study found a usage rate of about 68%. Average daily cost of energy due to air leakage at MIT was $13.10 during the winter, but a 75% usage rate of revolving doors drops the cost to $7.66, while 100% usage would drop it to $2.83.
Thus, two revolving doors at one building could save almost $7,500 yearly in natural gas used to heat and cool, amounting to nearly 15 tons of CO2 emissions.
A revolving door retrofit can be performed in weeks, Thomas says, but motivation to do so depends on a number of factors.
Space, Traffic, and Operations Considerations
The AAADM defines high traffic as more than two persons per minute moving through an opening and could also include equipment such as grocery carts or wheelchairs. Medium traffic is one person per minute, and low is one person every five minutes. Automatic and revolving doors are more ideal than swing doors at accommodating two-way traffic.
“Entertainment venues, educational facilities, and public transportation stations that get large rushes of crowds at peak times can benefit greatly by easing the funnel of people coming and going,” Moerbe says.
Neither automatic nor revolving doors require the space needed for a traditional door to open, the swinging of which also presents a traffic hiccup and safety concern. The vestibule configuration of automatic doors and the chamber style of revolving doors also make for a cleaner, quieter lobby because they aren’t directly open to wind and street noise.
Because of stack pressure and the chimney effect, swing doors can also be difficult to open, Thomas adds. “When a building is heated, the hot air rises, and pressure sucks the door in,” she explains.
“Powered door entrances do away with the aggravation and struggle of dealing with a heavy, manual door,” Moerbe adds. “They also demonstrate to users that the establishment they’re entering cares about their convenience.”
Enhancing Image and Aesthetics
“Automatic doors can help position a company as a leader,” Moerbe says, noting that for businesses serving older demographics, powered doors can provide a significant competitive advantage.
Businesses that welcome customers – especially the elderly and disabled – with an auto open and close enhances user experience, says Moerbe.
Both automatic and revolving doors are also more modern than traditional entrances and can jazz up your exterior.
“Consider whether the door design adds character to your facade,” Thomas says, adding that offerings can be customized with bronze, chrome, paint, or different glass. Both options are popular in downtown and high real estate markets, attracting high-paying tenants and occupants.
“Powered entrances can be very stylish,” Thomas says. “The door is the first thing people see, so it’s also the first feeling they have for the whole building.”
Chris Curtland is the former assistant editor of BUILDINGS.