Integrating Life Safety and Security Systems

Designing Effective Stairwell Re-Entry Systems in High-Rise Buildings

Most building owners concerned with security should opt for designing a stairwell re-entry system. Although this option is more expensive, it will provide their occupants with a more secure environment while helping ensure their safety during emergency situations.

Elements of the Stairwell Re-Entry System
Owners of high rises with either no security in their stairwells or locked stairwell doors should look for assistance from professional engineering firms to design a stairwell re-entry system that ensures stairwells will fully comply with the current local and national building codes. Professional engineering consulting firms with expertise in life safety and security can help building owners correctly identify the existing stairwell deficiencies and design a compliant system.

Prior to starting the design of the stairwell re-entry system, building owners should review the following basic elements that will factor into the design.

Building Fire Alarm Panel. What type of fire alarm is currently installed at the building? Regulations require that fire alarm systems be installed in all new high-rise construction or at the time of building retrofit. Addressable fire alarm systems allow the local fire department to determine where the fire alarm condition is occurring, and they also provide the capability to alert the affected occupants. The type of fire alarm system installed inside a building is a critical factor in determining how stairwells will unlock in a fire emergency.

Building Security Philosophy. What level of security is required for the occupants of the buildings? In high-rise financial buildings, the occupants may require the stairwells to be secured at all times, while residential building occupants may prefer to have the stairwells and floors accessible to allow for interflow between floors.

Stairwell Door Hardware. What kind of door hardware is presently on the stairwell doors? It is required that stairwell doors have latching hardware to ensure that in the event of an emergency the loss of power will not create a breach of the fire barrier and smoke control, rendering the exit stairwell unsafe.

Stairwell Door Construction. Do the exit stairwell doors and door frames meet the code requirements for fire ratings? Fire-rated doors may or may not be currently installed on stairwells to create a fire barrier between the stairwell and the adjacent floor. As part of the stairwell re-entry system, owners should review the door construction and replace existing non-compliant doors with doors that meet the requirements outlined in the local building codes. Without proper fire-rated doors, the exit stairwells may not provide a safe route of egress during a fire emergency.

Stairwell Re-Entry Solutions
Owners of high-rise buildings have three options when retrofitting or designing a stairwell re-entry system. Each option has pros and cons, but each provides the essential elements of stairwell re-entry upon alarm.

Free Egress. The simplest means to ensure stairwell re-entry during an emergency situation is to keep the stairwell doors unlocked, but latched at all times. Pros: This solution provides the ownership with the quickest and easiest method to ensure occupant safety during emergencies. This solution also is most cost-effective method to provide stairwell re-entry. Cons: This option does not provide any level of security to the building occupants on a daily basis. Not securing the stairwells allows any person that enters the building to access the stairwells on any floor.

Electrified Locksets. In this option, the stairwell is kept in a closed, latched and secured condition at all times. The occupied side of the door is unlocked to allow free egress from the floor into the stairwell. The stairwell-side door hardware is kept locked to prevent entry onto the floor. Upon activation of the building fire alarm panel, power is interrupted to the door power supply and the stairwell-side door hardware is released to allow entry from the stairwell onto the floor. Pros: This design involves equipment that can be purchased from numerous vendors throughout the United States. It is a suitable method for new-construction buildings or situations where the entire door needs to be replaced. Card reader technology can be easily added to require authorized access from the stairwell onto the floor. Cons: This option requires extensive door modifications to run wiring from the external power supply to the door handle.