Building access can be blocked partially or completely during a fire or other emergency situations, which means firefighters need alternate ways to enter or leave the building. Since rooftops can be used for these purposes, the NYC Fire Code establishes minimum clearances and accessibility requirements.
Rooftops covered by article 504 of the NYC Fire Code must have clearances for FDNY access. This means mechanical equipment and other external components must be installed where they will not block the required clearances. The same logic applies for rooftop solar power systems and vegetation.
The clearance dimensions required in the NYC Fire Code may seem large at first, but consider all the tools and equipment that firefighters must carry around during an emergency.
Does your rooftop provide the clearances required by the FDNY?
Why Are Rooftop Clearances Required?
Rooftop clearances serve three main purposes for the FDNY: simplifying rescue operations, vertical venting of heat and smoke, and unobstructed access for the inspection of rear yards, courtyards and other uncovered areas not visible from the street.
Rescue operations are less difficult when firefighters have more mobility. For example, assume some persons must be rescued from a room where there is a window overlooking a courtyard.
Without rooftop access, firefighters must reach the persons through the building interior. This may involve avoiding obstacles, fire and falling objects.
On the other hand, with rooftop access it is possible to reach the spot above the trapped persons, and simply rescue them through the window.
Both hot air and smoke tend to rise, but during a fire they may be trapped in unvented building areas. Human beings avoid fire and heat by instinct, but the dangers of smoke are often underestimated. In addition to limiting visibility, smoke contains combustion by-products that can cause unconsciousness. A common method used by firefighters to release trapped heat and smoke is cutting open the rooftop above the affected area.
When there is an emergency and the main building exit is far away or hard to reach, occupants often seek safety by gathering in open areas like courtyards and rear yards. Firefighters can survey these areas much more easily with rooftop access.
When Are FDNY Rooftop Clearances Required?
The NYC Fire Code makes rooftop clearances mandatory for buildings with a height of 100 feet or less. However, if the ceiling has a slope of more than 20 degrees, the property is exempt from the requirement.
The FDNY rooftop clearance requirements were not made mandatory for existing rooftops when published in July 1, 2008. However, they apply for all new properties and any renovation or alteration of an existing rooftop. If you upgrade part of an existing rooftop or modify roof-mounted equipment in any way, clearance requirements apply for the entire rooftop area, not only the affected section.
The project design must be submitted to the NYC Fire Department for approval. Even if the design meets the NYC Fire Code, you cannot proceed before the corresponding approval procedure.
Overview of Rooftop Access Requirements
Before describing the requirements of the NYC Fire Code, it is important to understand the concept of frontage space: the staging area for firefighting or other emergency operations, located in front of a building. To be considered frontage space, the area must meet the following conditions:
A width of at least 30 feet.
Access from the street or from a fire apparatus access road.
Free from any obstructions that hinder firefighters, such as plant boxes and fences.
The frontage space is generally a portion of the street in front of a property, but any open space meeting the required conditions can be considered frontage space. The following table summarizes the main requirements to make rooftops accessible for firefighters.
A) The front wall of the building and any walls accessible from the frontage space must have a 6-ft wide clearance for every 12 ft of perimeter. Any ground level obstacles must be separated from the wall by at least 6 ft as well, and the rooftop must have a landing area of at least 6 ft x 6 ft.
B) If the accessible building perimeter is at least 24 ft but less than 36 ft, separation between clearances must be 12 ft.
C) If the accessible perimeter is 36 ft or more, contiguous openings are allowed. Their combined width must not exceed 12 ft and they must be separated from other clearances by 12 ft.
A) For every 100 ft of rooftop width or depth, there must be a clear path across the building with a minimum width of 6 ft. The path must completely cross the building front-to-back or side-to-side, and it must also have an unobstructed height of 9 ft above the ceiling.
B) These clear paths must be protected with railings, and provide reasonable access for potential entry points such as bulkheads and skylights. The path can be blocked by a fence with a 3 ft wide gate opening inward, as long as the chain or lock can be cut easily by firefighter equipment.
C) If the rooftop has different levels, the clear path can be connected across levels with a fixed and noncombustible ladder.
CONDUIT AND PIPING
A) Any conduit or raceway on the ceiling must be installed so that it does not hinder movement for firefighters. The NYC Fire Code allows conduit or raceway across clear paths if avoiding them is not possible, but there are several requirements to minimize the risk of tripping.
B) If conduit or raceway crosses the clear path, the maximum height is 1 ft and the maximum width is 24 in. If the obstacle exceeds these dimensions, stairs or a ramp must be installed to simplify movement.
C) Conduit and piping must be color-coded with luminescent or reflective waterproof markings, so that FDNY personnel is aware of the contents.
Red for high voltage
Orange for low voltage
Yellow for natural gas.
Yellow with labels at regular intervals for other compressed gases.
Yellow with black stripes for fuel oil.
For any door leading to the rooftop, a minimum clearance of 6 ft measured from the door hinge is required.
The clearance for fire escapes and rooftop ladders is 3 ft, measured from the sides in all directions.
SOLAR POWER SYSTEMS
Solar panels in flat roofs can cover the clear paths, as long as they have a mechanism that allows one person to move them out of the way without tools. In buildings with a slope of more than 20 degrees, the requirement is leaving a 3 ft clearance between solar panels and the ridge. These are only general requirements, but the NYC Fire Code dedicates article FC512 exclusively to clearances around solar panel systems.
New York City is characterized by its stringent fire protection requirements, and mistakes during the design phase can lead to many revisions and change requests by the FDNY. Delays during the design and approval process can lead to a delayed construction and start of operations, so it is in your best interest to get the project approved on the first try or with minimal changes.
At Nearby EngineersNew York Engineers , we search for simple, eloquent solutions to complex problems. We minimize construction costs by eliminating the extraneous and focusing on the overall efficiency for the most streamlined designs.