24 175262 ALT

Project Description

An interconnected floor space is proposed to be located between Level 4 and Level 5 of the addition to accommodate a convenience stair.In accordance with Sentence 3.2.8.2.(5), openings for stairways, escalators and inclined moving walks need not conform to the special atrium requirements provided:a) the opening for each stairway, escalator or walk does not exceed 10 m2,b) the building is sprinklered throughout, andc) the interconnected floor space contains only Group A, Division 1, 2 or 3, Group D or Group E occupancies.The proposed interconnected floor space will satisfy the above requirements with the exception of the floor opening exceeding the permitted maximum of 10 m2 in area. It is noted that the City of Toronto has previously approved floor openings of up to 20 m2 as an alternative solution.The above approach is considered to perform as good as the prescriptive allowances for a 10 m2 opening in consideration that:The OBCa) does not limit to the number of 10 m2 floor openings,b) does not stipulate proximity limits of multiple floor openings, andc) does not limit the number of storeys interconnected by these openings.The proposed interconnected floor space will bea) equivalent to two side-by-side permitted openings,b) limited to include only two storeys,c) protected by draft stops and water curtain sprinklers per NFPA 13 for small openings that are not otherwise permitted (not required by NFPA 13 for a permitted 10 m2 opening),d) Each floor area is protected by smoke detection within public areas (not required for a 10 m2 opening), and The second exit from L4 and L5 is remote from floor opening and provides additional capacity.

Permit Details