It’s heavy and rotates slowly, so what are the advantages of a building’s revolving door?

Audit expert: Zheng Fang

Chief Architect of Beijing Jiaotong University Architectural Survey and Design Institute

Chief Designer of Ice Ribbon and Ice Cube

In daily life, whether we are heading to a shopping mall or an office building, we often see those huge and eye-catching revolving doors at the entrances of busy buildings such as shopping malls and office buildings. From the appearance, revolving doors seem large and bulky. Why do building designers choose to use them?

Source: pexels

In fact, the existence of this kind of door is not meaningless, but has its unique advantages and value. Let us explore the reasons together.

Benefits of installing a revolving door

Firstly, revolving doors can become an iconic element of a building. Whether it is at the entrance of a skyscraper or in the lobby of a five-star hotel, the design of these revolving doors is carefully considered. Their presence can leave a deep impression on people in various perceptual channels and become one of the characteristics of the building.

The architects chose to use revolving doors not only to fulfill their function as entrances and exits, but also to form air locks to reduce the amount of outside air entering the building , achieving energy conservation and indoor environmental control.

Source: pixabay

Revolving doors have excellent air isolation and energy-saving functions. Compared with traditional sliding doors, revolving doors are open for a shorter time and have the characteristic of "opening and closing" in structure. Therefore, the design of this door can effectively prevent the cross-flow of indoor and outdoor air, reduce the penetration of airflow, and reduce the direct blowing of cold or hot air into the room, especially in areas with obvious alternation of hot and cold climates. This not only reduces the discomfort of cold and hot air to people entering or leaving the building, but also reduces the load of indoor air conditioning or heating systems, which is very useful for maintaining a stable temperature inside the building and reducing energy waste, further improving energy efficiency.

The invention of the revolving door

As a special entrance and exit design, the invention of the revolving door can be traced back to the late 19th century. During this period, people began to pay attention to the problems of traffic flow management and energy conservation in buildings, and needed to improve the entrance and exit design. The concept of revolving door came into being.

In 1882 H. Bockhacker patented the "ventilationless door" (Thür ohne Luftzug) in Berlin, which was essentially a revolving door.

Six years later, in 1888, Theophilus Van Kannel of Philadelphia, Pennsylvania, received a patent for his "four-wing door construction" - writing in his patent application: The storm-proof door construction has many advantages over the hinged door construction of common character, because the door is close to the casing and is completely noiseless in operation, and is effectively prevented from entering by wind, snow, rain or dust, both when it is closed and when a person is passing through it. Moreover, the door cannot be blown open by the wind, because the pressure on both sides of the center of movement is equal.

Source: media.snopes.com Theophilus Van Kannel subsequently patented several improvements and enhancements to the revolving door, founded the Van Kannel Revolving Door Company, and died in New York City on Christmas Eve 1919 at the age of 78.

This invention was subsequently widely recognized and applied, and is commonly used in busy places such as shopping malls, hotels, and banks, demonstrating excellent traffic flow management and convenience.

As time goes by and technology advances, the design of revolving doors continues to improve. In addition to buildings, revolving doors are also widely used in railway stations, airports and other public transportation places. In these places, revolving doors are usually designed as one-way fences to control the direction and amount of people flow.

The revolving doors in railway stations and airports are mainly used to manage large numbers of passengers safely and conveniently. By setting up a one-way revolving door, it can ensure that passengers enter and exit in the designated direction, avoiding congestion and chaos. This design can also effectively prevent illegal entry and improve security.

Some revolving doors are even equipped with additional features, adding more safety features, automated controls, and more efficient and energy-saving operations, such as automatic opening and emergency evacuation in emergencies.

Disadvantages of revolving doors

Of course, revolving doors are not without disadvantages. Although they have many advantages in terms of facilitating people to enter and exit buildings and controlling the flow of people, they also have some potential problems and risks. During peak hours, revolving doors can be crowded, and people may be pinched or trapped . For users such as the elderly, children, and the disabled, it is more likely to be dangerous.

Many children will treat the revolving doors in shopping malls or hotels as toys and play chase games with their friends. In Fuyang, Anhui, two children were chasing each other through the glass in a revolving door. The 8-year-old girl wanted to run out with her friends, but was caught in the revolving door and was eventually diagnosed with a torn right ear.

Source: News Photo

In 1942, a popular Boston nightclub caught fire when a revolving door got stuck and there were no swing doors next to it. 492 people died from smoke inhalation.

After this incident, regulations in various countries have regulated revolving doors in buildings to ensure safety in emergency evacuation situations. The regulations clearly state that revolving doors should be equipped with an emergency stop button to immediately stop the movement of the revolving door in an emergency, and an emergency opening mechanism to enable manual opening of the door when necessary. The regulations also require that sufficient emergency escape routes, such as swing doors, be provided near the revolving door to ensure that people can leave quickly.

In addition, because revolving door entrances are usually narrow, they may not be user-friendly for people with limited mobility, people who use wheelchairs or other assistive devices, or people who carry large items or luggage. These people may need additional assistance or use other means of access.

For designers and operators, paying attention to and solving these problems is an important task to improve the performance and user experience of revolving doors. At the same time, users should also consciously abide by the rules of revolving door use and remain vigilant to ensure the safety of themselves and others. The existence of revolving doors not only adds a unique charm to the building itself, but also brings people a convenient and safe social experience.