Rooftop stairs are an integral part of many building designs, offering practical access to the rooftop. These can be used for maintenance, leisure, emergency escape routes, and more, depending on the building’s design and purpose.
Rooftop stairs, or stairs that lead up to the rooftop of a building, serve a variety of functions depending on the type of building and its uses.
What are the primary uses:
- Access to Rooftop Equipment: Many buildings house their HVAC units, solar panels, antennas, and other such equipment on the roof. Rooftop stairs provide a safe and convenient means of accessing these units for maintenance, repair, and inspection.
- Rooftop Gardens or Amenities: In urban environments, rooftops are often transformed into usable spaces like gardens, lounges, swimming pools, or restaurants. Stairs are needed to provide access to these amenities.
- Emergency Exit: In certain cases, rooftops can serve as emergency evacuation points. For example, in high-rise buildings, a helicopter might be used for evacuations when exits at ground level are blocked. In such cases, rooftop stairs serve as an essential part of the building’s fire safety measures.
- Viewpoints: In buildings such as hotels or residential towers, the rooftop may be used as a viewing platform or observation deck. Stairs would be used to provide access to these spaces.
- Access for Construction and Maintenance: Rooftop stairs can provide access for construction crews during the building’s construction or renovation phases, and later for maintenance crews for tasks such as cleaning, painting, or repairing the building’s exterior.
- Firefighter Access: In the case of a fire, it may be necessary for firefighters to access the rooftop to fight the fire from above, ventilate the building, or rescue occupants.
- Rooftop Events: If the rooftop is used for events or gatherings, stairs provide the needed access for attendees and staff.
While the design and construction of rooftop stairs need to account for regular use, they must also adhere to safety regulations to ensure they can safely be used during emergencies.
Just like fire escape staircases, rooftop stairs must also comply with regulations and standards set by organizations like the Occupational Safety and Health Administration (OSHA) and the International Building Code (IBC) to ensure safety and accessibility. Below are some general requirements that these stairs should meet:
OSHA Compliant Rooftop Stairs:
- Width: The minimum width of stairs should be 22 inches.
- Handrails: Stairs with four or more risers, or that rise more than 30 inches, should have at least one handrail. If the width of the stairs exceeds 44 inches, it must have a handrail on both sides.
- Maintenance: Stairs should be free from hazards like sharp or protruding objects, and they should be kept clear of debris or materials that might cause someone to slip, trip, or fall.
- Landing: The landing width must be no less than the stair width and have a length of at least 30 inches.
IBC Compliant Rooftop Stairs:
- Width: The minimum width is typically 44 inches, but this may vary depending on the expected occupant load.
- Handrails: Stairs must have handrails on both sides. The IBC provides specifications on the size, shape, and placement of handrails.
- Landings: Staircases must have a landing at the top and bottom. The landing should be at least as wide as the stairs and at least 36 inches in the direction of travel.
- Risers and Treads: There are specific measurements for the height (riser) and depth (tread) of each stair to ensure they are safe and comfortable to use. For example, risers must be no more than 7 inches high and treads no less than 11 inches deep.
- Headroom: The minimum headroom in all parts of the stairway shall not be less than 6 feet 8 inches.