BCAB #1715 - Width of Access to Exit Stairs, Article 3.3.1.17.

July 10, 2012

BCAB #1715

Re: Width of Access to Exit Stairs, Article 3.3.1.17.

Project Description

The project in question is a suite for a child and infant day care centre on the second floor of a new multi-tenant commercial building. The day care centre has been classified as a Group B Division 2 Care occupancy because it is licensed for up to 36 infants who are too young to understand directions for evacuation or physically unable to walk out on their own. Rather than the typical public corridor called for by Sentence 3.3.1.3.(8) egress from the suites is via interior exit stairs from every suite leading to ground level. One exit stair is only for the use of the day care while a second exit stair is shared with the adjoining suite. The occupant load of the day care is 104.

Reason for Appeal

Sentence 3.3.1.5.(1) requires the day care suite to have two egress doors located such that if one is blocked by a fire in the suite the other door remains accessible. Sentence 3.3.1.17.(5) requires the capacity of the egress stairs to be determined in accordance with Sentences 3.4.3.2.(1) to (3). Sentence 3.4.3.2.(2) requires the aggregate width of exits serving care occupancies to be determined by multiplying the occupant load by 18.4 mm per person. Sentence 3.4.3.2.(7) requires that where more than one exit is required no exit shall be considered to provide more than half the required exit width. The appeal concerns the relative width of the two egress stairs.

Appellant's Position

The appellant contends that the two stairs as designed will accommodate the occupant load of the day care centre including a portion of the adjacent suite’s occupant load in the shared stair. The stairs provide egress directly from the suite and should not be required to conform to Sentence 3.4.3.2.(7) because they function the same as access to exit from a suite where there is no restriction on the percentage of occupants per egress facility. The design is adequate to take 42 people from the day care centre in the shared stair and 62 people in the stair serving only the day care centre.

Building Official's Position

The building official maintains that Sentence 3.4.3.2.(7) applies because the stairs are exits, not access to exits. As both stairs are already constructed, an occupant load of 104 will require the existing exit capacity to be supplemented in order to conform to Sentence 3.4.3.2.(7).

Appeal Board Decision #1715

The Board notes the building does not conform with the access to exit requirements of Sentence 3.3.1.3.(8) and the suites rely on direct exits from their floor spaces. This being the case the Board considers that the principles for exits in Section 3.4 must be applied and the exits from the suite in question must conform with Sentence 3.4.3.2.(7).

George Humphrey, Chair