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BCC Ruling No. 98-20-625

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IN THE MATTER OF Subsection 24 (1) of the Building Code Act, 1992.

AND IN THE MATTER OF Clauses, and of Regulation 61, as amended by O. Reg. 400/91, 158/93, 160/93, 383/94, 20/95 and 395/96 (the "Ontario Building Code").

AND IN THE MATTER OF an application by Mr. Roul Martjak, Senior Clerk of Work, Toronto District School Board (Formerly York Board of Education), Toronto (York), Ontario for the resolution of a dispute with Mr. Bruce Ashton, Chief Building Official, City of Toronto (York), Ontario to determine whether the unenclosed walkway in the proposed two storey school structure provides sufficiency of compliance with Clauses, and of the Ontario Building Code at The Clouston Schools, 100 Sidney Belsey Crescent, Toronto (York), Ontario.


Mr. Roul Martjak, Senior Clerk of Work
Toronto District School Board (York Board of Education)
Toronto (York), Ontario


Mr. Bruce Ashton
Chief Building Official
City of Toronto (York)


Mr. Roy Philippe (Chair)
Ms. Susan Friedrich
Mr. Ross Thomson


Toronto, Ontario


May 6, 1998


May 6, 1998


Mr. Dave Syrett, Senior Associate, Leber Rubes Inc.
Toronto, Ontario
Agent for the Applicant

Mr. Richard Chiu, Building Plan Examiner
City of Toronto (York)
For the Respondent


  1. The Applicant

Mr. Roul Martjak, Senior Clerk of Work, has applied for a building permit under the Building Code Act, 1992 to construct a new, two-storey, elementary and middle school at 100 Belsey Crescent, Toronto (York), Ontario.

  1. Description of Construction

The Applicant proposes to construct a new, two storey school with two wings, the east wing serving as an elementary school and the west wing as a middle school. The wings are joined by a large general purpose room and a solarium, which includes a second floor walkway linking the two schools. The proposed walkway is unenclosed, thus acting essentially as a second storey bridge spanning the main entrance lobby, or solarium. It also overlooks the adjacent general purpose room. The walkway is necessary because it allows both schools to access the exit stairs provided at the south end of the second floor corridors. Without the walkway, these corridors would otherwise terminate at their southern end.

The bridge itself will be 30 metres long, 4 metres wide, and 3.8 metres above the floor of the solarium. The floor of the bridge is proposed to have a 1 hour fire resistance-rating, as measured from the underside. Each end of the walkway is fire separated from the second floor with a 30 minute rating.

The proposed building has a building area of 5,990 m2. It is to be built of noncombustible construction, with the exception of the heavy timber proposed for the roof area over the general purpose room and the solarium. The building is equipped with a fire alarm and detection system, an automatic sprinkler system and is considered to face one street. The structure is classified as a Group A, Division 2, school occupancy.

  1. Dispute

The issue at dispute between the Applicant and Respondent is whether the proposed walkway is allowed to be unenclosed under the 1990 Ontario Building Code, in particular Sentence To elimate dead-end corridors. This provision allows interconnected floor space under certain conditions, one of which is that floor openings adjacent to a corridor must terminate at a fire separation rated at 30 minutes. If the bridge is viewed as a part of the corridor system, then applies and a 30 minute fire separation extending from the floor of the walkway to the underside of the ceiling above must be provided. However, if the bridge can be considered as a mezzanine, then does not apply and no fire separation is required.

  1. Provisions of the Ontario Building Code

Sentence Floor Space in Schools

(c)the portions of the upper floor area that do not terminate at an exterior wall, a firewall or a vertical shaft shall terminate at a vertical fire separation extending from the floor assembly to the underside of the floor or roof assembly above,

(e)where a corridor is located immediately adjacent to the fire separation required in Clause (c), the fire separation shall have a fire-resistance rating of not less than 30 min, and

(f)where a portion of a floor area is not within the interconnected floor space, the required access to exit from this portion of the floor area shall not lead through the interconnected floor space.


A dead end corridor is permitted in an assembly occupancy where there is a second and separate egress doorway from each room or suite not leading into a dead end corridor.

  1. Applicant's Position

The Applicant submitted that the proposed walkway need not be enclosed and provided with a 30 minute fire separation. In their view, the open bridge provides sufficiency of compliance with the 1990 Ontario Building Code for the following reasons.

The Applicant argued that the corridors in the southern portions of the second floor of each school wing do not truly represent dead-end conditions due to the fact that an alternate exit is available via the proposed bridge for both schools in the event of an emergency. They noted that each wing has two exit stairs and the bridge would allow occupants to travel to exit stairs on the other side of the building if the ones on their side were blocked.

As the Applicant pointed out, it would be unlikely that a fire emergency on the second floor in one wing of the school would affect both the bridge and the other wing at the same time, thereby making the circumstances that could cause a dead-end situation extremely remote. Similarly, an emergency in the solarium or the general purpose room would simply mean that occupants would use either of the two exit stairs provided in their wing. Further, the 30 minute fire separation proposed for each end of the bridge would allow occupants time to use the exits provided in their wing of the building.

The Applicant also noted that the solarium and the general purpose room will have limited combustible fire loads. As well, these two rooms will be separated from the classroom wings by a 30 minute fire separation.

Essentially, the Applicant contended that the bridge could be considered as an open mezzanine within the solarium and general purpose room since, in their opinion, the proposed bridge satisfies Sentence of the OBC regarding mezzanines. To support this assertion the Applicant noted that the bridge, at 120 m2, is only 12.5 % of the 960 m2 room in which it is located, will be used as an open floor area, and will be provided with a 1,070 mm guard on both sides.

It follows, the Applicant argued, that an open mezzanine is not subject to the interconnected floor space requirements found in Sentence of the Code, in particular the 30 minute vertical fire separation where a floor opening is adjacent to a corridor. Specifically, they pointed out that the proposed bridge complies with Clause which permits an open mezzanine not to terminate at a vertical fire separation where every point on the mezzanine is within 25 metres of a point that can allow an occupant to view 60 % of the room, and is not a Group B occupancy.

The Applicant also discussed Sentence which requires that every mezzanine without a vertical fire separation shall have two egress facilities placed in such a manner that at least one be accessible in certain situations. On this point, the contended that the proposed bridge will have better egress than that required under this provision of the OBC.

The Applicant conceded that a strict interpretation of the Code may lead one to believe a 30 minute fire separation is required for the bridge in question. Based on the reasons described above, however, the Applicant is of the belief that proposed walkway provides sufficiency of compliance with the relevant provisions of the Building Code.

  1. Chief Building Official's Position

The Respondent submitted that the proposed bridge is part of the corridor system of the school and thus OBC applies, making a 30 fire separation at the walkway edges mandatory.

In the Respondent's view, the two second floor corridors at the school's south end have dead-end conditions. As they note, there are no second and separate egress doorways from each room that does not lead into the corridor, as required under Sentence Further, the requirement found in Clause prohibits an access to exit within an interconnected floor space. Assuming that the bridge is a mezzanine, i.e. considered to be part of the first storey, within the solarium and the general purpose room also did not satisfy the Respondent that a second means of egress could be established. They pointed out that as part of the first storey, the bridge cannot serve as a means of exit for corridors on the second floor, unless the penetration between storeys is by means of an exit conforming to Section 3.4, which under Sentence requires a 1 hour separation.

The Respondent submitted a letter from the Applicant's agent stating that the 30 minute fire separation in question would be built in return for the Respondent considering the generalpurpose room and the solarium as a combined space for determining occupant load. At the time, the Respondent noted that the Applicant agreed to considered these two spaces as not serving as an access to exit from either school. In the Respondent's view, the proposal at hand violates these two agreements.

The Respondent also expressed concerns about the proposed unenclosed walkway because they felt that the heavy timber roof assembly and the combustible flooring of the general purpose room represented enough of a combustible load that occupants travelling across the bridge would be exposed to dangerous levels of smoke.

The Respondent rejected the Applicant's argument that the bridge can be viewed as a mezzanine. While admitting that the bridge may have appeared to have met the open mezzanine requirements, it was their belief that it is the intent of the Code that the interconnected floor space requirements of should apply to this situation. They cited the 1997 version of the OBC, claiming that the new Code has made it clearer that the interconnected floor space standards are applicable in this circumstance.

  1. Commission Ruling

It is the decision of the Building Code Commission that the unenclosed walkway serving as an alternate access to exit from the second floor school building does not provide sufficiency of compliance with Sentence

  1. Reasons

i)The walkway is a required access to exit from the second storey to eliminate dead-end corridors.

ii)As a corridor it is required to be separated by a fire separation having a 1/2 hour fire resistance rating from the remainder of the building, as required by Sentence

iii)No alternate measures were included to compensate for the life safety hazard of exiting through an interconnected floor space via an open bridge in an elementary school.

Dated at Toronto this 6th day in the month of May in the year 1998 for application number 1998-14.

Mr. Roy Philippe, Chair

Ms. Susan Friedrich

Mr. Ross Thomson