CHOOSING A REVOLVING DOOR:
Typically, potential traffic flow through doors is based on the diameter, the number of persons that will fit in each of the segments, all segments being filled, and the speed stipulated by code. However, cultural psychology and typical baggage is more of a determinant for flow. It is best to assess type of traffic; for example, professional – persons with briefcases; social - mothers with strollers, or institutional – gurneys and/or wheelchairs.
Revolving doors must be equipped with a speed regulator to prevent the door from rotating faster than the following speeds. Refer to ANSI Standard A156.27 for industry accepted door speeds.
A manual small-diameter revolving door is conveniently chosen for high-mid and low-rise office buildings. It is also used for retail entrances, theaters and other such applications. The small diameter revolving door ranges between 1828 mm (6’0”) diameter to 2438 mm (8’0”) diameter. This diameter features three or four-wing configuration. However, consider segment size restriction and code requirements when choosing four wings on a small diameter door.
A mid-diameter revolving door is used for airports and hotel applications and ranges from 2438 (8’0”) to 3048 mm (10’0”) in diameter. This size may feature three or four-wing design and may be manual, power assisted or automatic.
A large-diameter revolving door ranges from 3048 mm (10’0”) to 3658 mm (12’0”) and is used in high traffic, high baggage volume areas such as airports, large hotels and hospitals. These doors are fully automated and have extensive safety features. Large-diameter doors can be three or four-wing designs.
A security (access control) revolving door is used in entrances requiring different levels of security. Security is maintained by use of sensors detecting ingress and egress. Card reading access systems are most common and are augmented by sensor mats and door arm sensors to pick up weight discrepancies and “anti -tailgating.” New e-security sensing systems offer “anti -piggybacking.”
*Note: When specifying automatic or security revolving doors, it is important to specify all required functions. These requirements should be noted on all shop drawings and should meet specific expectations of the end user.
Number of Wings
Three-wing revolving door design offers larger segments of passage and is often considered for hotels and airports where usage requires passage of baggage, carts or wheelchairs. Note: Three-wing models have a smaller entry and exit opening and therefore 2 units are recommended for in/out flows.
Four-wing revolving door design allows for a more controlled flow of traffic. This design has the added benefit of a superior weather seal and less air infiltration in the closed position (quarter-point closing).
Revolving Door Configuration
Every revolving door has basic components regardless of style and size. It is topped with a canopy, which is the structure above the wings and enclosure. This consists of a roof or deck cover, fascia and soffit. The canopy can be designed in a variety of heights and configuration and is made of glass or metal (or a combination of both).
Door wings or leaves are the panels that rotate within the enclosure. The wings are attached to the centre shaft, which is the rotating centre of the revolving door. The enclosure (drum wall) is the frame for the bent curved glass and reaches between the floor and canopy.
The speed control can be located overhead or is floor mounted. This device regulates the rotation speed of the wings as set by standards. North American codes allow a maximum RPM for a revolving door depending on diameter (10 RPM on an 8’ diameter door, for example). Pivot bearings are used in conjunction with a speed control to ensure precise and smooth rotation.
Bookfold refers to the collapsing action of the wings to release and pivot in the direction of egress. This mechanism is critical for safety and is required by fire/building codes on all entrance revolving doors installed in North America, when the revolving door is part of the building egress.