Stairwell Roof Fire Rating

The term stairwell reentry refers to the code requirements which allow a building occupant to leave a stairwell during a fire emergency and find another exit.

Stairwell roof fire rating.

In buildings four or more stories or more than 40 feet 12 192 mm in height above grade one stairway shall extend to the roof surface through a stairway bulkhead complying with section 1509 2 unless the roof has a slope steeper than 20 degrees 0 35 rad access to setback roof areas may be through a door or window opening to the roof. Interior exit stair ways shall be enclosed. Vertical exit enclosures four stories or mor e shall be 2 hour fire resistance rat ed. What i found is still somewhat inconclusive.

Fire ba rri er wal ls shall ext end f rom the top of the floor cei ling assembly below t o the under side of the floo r or roof slab or deck abo ve and shall be securely attached thereto. 05 31 06 706 4 co ntinuity o f fire ba rrier w alls. If stairwell doors do not allow for reentry and a stairwell becomes impassible it can jeopardize the lives of those using the stairwell as a means of egress. The number of stories shall be co mp uted as al l f loor lev els i ncludi ng bas ements but ex cludi ng mezzan ines.

3 every exit shall be separated from the remainder of the building by a fire separation having a fire resistance rating not less than that required by subsection 3 2 2 but not less than 45 min for a the floor assembly above the storey or b the floor assembly below the storey if there is no floor assembly above. 06 06 2003 edition issued. Can you rate the ceiling or lid of a stair or elevator enclosure thus avoiding the expense and complication of taking the rated walls to the bottom of the roof. Over non combustible roof decks such as steel poured gypsum or concrete only the spread of flame on the top surface of the roof system is evaluated.

Astm e119 standard test methods for fire. Fire resistance rated construction section 706 4 ibc interpretation no. The maximum flame spread is 6 feet for a class a rated roof 8 feet for class b and 13 feet for class c. Fire and sound selector fire and sound ratings fire ratings fire resistance is the ability of an assembly constructed in a laboratory to contain a fire in a carefully controlled test setting for a specified period of time.

Ver tical exit enclosur es les s than f our stor ies shall be 1 hour f ire resistance rated. Openings in the roof shall not be located within 4 feet 1220 mm of the fire wall.