Nook Coverage

[indyarchyguy]

I have a client that would like to create a nook for their dog at the office. The nook would be located under a stair adjacent to the office space. The walls of the stair are constructed with a 1-hour rated UL assembly. The ceiling of the nook (under the stair) is also rated 1-hour. The question is whether a sprinkler is required within the nook? The nook would be approximate 36-inches deep. The question is at what head clearance would a sprinkler head under the stair be triggered? For some reason I thought 44-inches maximum height...but I am unsure. NFPA 13 - 2010 edition here.

 

[classicT]

Perhaps you could attempt to justify per the IBC/IFC. See Section 903.3.3.

2021 IBC [F] 903.3.3 Obstructed Locations​

Automatic sprinklers shall be installed with regard to obstructions that will delay activation or obstruct the water distribution pattern and shall be in accordance with the applicable automatic sprinkler system standard that is being used. Automatic sprinklers shall be installed in or under covered kiosks, displays, booths, concession stands, or equipment that exceeds 4 feet (1219 mm) in width. Not less than a 3-foot (914 mm) clearance shall be maintained between automatic sprinklers and the top of piles of combustible fibers.​

Exception: Kitchen equipment under exhaust hoods protected with a fire-extinguishing system in accordance with Section 904.​

There is also the exceptions provided in 903.3.1.1.1, but I do not believe any of those would apply.

[F] 903.3.1.1.1 Exempt Locations​

Automatic sprinklers shall not be required in the following rooms or areas where such rooms or areas are protected with an approved automatic fire detection system in accordance with Section 907.2 that will respond to visible or invisible particles of combustion. Sprinklers shall not be omitted from a room merely because it is damp, of fire-resistance-rated construction or contains electrical equipment.​

1. A room where the application of water, or flame and water, constitutes a serious life or fire hazard.
2. A room or space where sprinklers are considered undesirable because of the nature of the contents, where approved by the fire code official.
3. Generator and transformer rooms separated from the remainder of the building by walls and floor/ceiling or roof/ceiling assemblies having a fire-resistance rating of not less than 2 hours.
4. Rooms or areas that are of noncombustible construction with wholly noncombustible contents.
5. Fire service access elevator machine rooms and machinery spaces.
6. Machine rooms, machinery spaces, control rooms and control spaces associated with occupant evacuation elevators designed in accordance with Section 3008.

 

[classicT]

For the exceptions provided in NFPA 13, see Chapter 9, Section 9.2 - Allowable Sprinkler Omission Locations.