Automatic doors are a common sight at grocery stores or other businesses where consumers enter and exit. These doors open automatically when people approach them using a motion sensor that triggers a device that slides the door open quietly. The door remains open for a few seconds and allows the person to walk through and then automatically closes behind them.
In addition to convenience for certain businesses, these doors also allow for a constant stream of traffic since the motion detectors will keep the door open until no one is moving in the direction of the door. Although the doors may stay open much of the time, they will close when not needed to keep as much of the warm or cool air inside as possible. The doors also remain clean because there is no need for hands to touch them.
Revolving doors are often located in hotels, malls or other buildings with moderate to heavy traffic. The revolving door is made to rotate counter-clockwise with traffic entering on the right side and then stepping between two "wings" of the door that rotate constantly with a motor or manually through pushing. The doors are constructed with flaps that create a light seal against the frame of the door so two of the wings are always in contact. This means the door is always open and always closed at the same time.
One of the advantages of a revolving door is the savings it can provide in heating and cooling costs. This type of door can save up to 25 percent on energy and heating costs, according to the International Revolving Doors website. On windy days, these doors will not fly open and become a nuisance.
Revolving doors handle high traffic and some have safety features that allow the wings to collapse and make an open door for quick exit.
When a building does not have concerns about heavy traffic, a standard door works well. A standard door is likely the type you find on a house with a door handle or knob with hinges that swing it open and closed. Depending on the construction material, these doors are quite secure and generally do not have many maintenance issues.