BUILDING CODE COMMISSION

Transcription

1 Ruling No Application No BUILDING CODE COMMISSION IN THE MATTER OF Subsection 24(1) of the Building Code Act, S.O. 1992, c. 23, as amended. AND IN THE MATTER OF Article and Sentence (1) of Regulation 403, as amended by O. Reg. 22/98, 102/98, 122/98, 152/99, 278/99, 593/99, 597/99, 205/00 and 283/01 (the Ontario Building Code ). AND IN THE MATTER OF an application by Michael Moldenhauer, Moldenhauer Developments, for the resolution of a dispute with Frank Asta, Chief Building Official, Town of Oakville, to determine whether the proposed compensating measures offered in a building containing A2 and D occupancies and having exposing building faces with unprotected openings less than 10% of the exposing building face and which includes elements of combustible construction, provides sufficiency of compliance with Article and Sentence (1) of the Ontario Building Code at Thomas Street, Oakville, Ontario. APPLICANT RESPONDENT PANEL PLACE Michael Moldenhauer Moldenhauer Developments Mississauga, Ontario Frank Asta Chief Building Official Town of Oakville Len King, Vice-Chair John Guthrie Gary Burtch Toronto, Ontario DATE OF HEARING August 1, 2002 DATE OF RULING August 1, 2002 APPEARANCES Leszek Muniak Larden Muniak Consulting Inc. Toronto, Ontario The Applicant Frank Asta Chief Building Official Town of Oakville The Respondent

2 -2- RULING 1. The Applicant Michael Moldenhauer, Moldenhauer Developments, has received a building permit under the Building Code Act, S.O. 1992, c. 23, as amended, and has constructed a double occupancy building at Thomas Street, Oakville, Ontario. 2. Description of Construction The Applicant has undertaken construction of a building, originally intended to be used as two, threestorey semi-detached dwellings. It is now the Applicant s intent that the building will contain both Group A, Division 2 and Group D occupancies. The structure is comprised of combustible construction and will be equipped with fire alarm and sprinkler systems. The construction in dispute involves the fact that combustible building materials have been used in the erection of this building, which will now be used for A2 and D occupancies. In particular, as a result of the original plan for the building as a Group C occupancy, the structure includes combustible wood framing and the application of stucco to the exterior walls. After the framing and enclosure of the building had been competed a new prospective purchaser advised that he was interested in obtaining the subject the building for assembly occupancy and office uses. Plans were subsequently revised to accommodate the new intended occupancies, however, the combustible framing and building cladding remains at issue. To compensate for the use of combustible construction where noncombustible materials are required the Applicant is proposing complete sprinkler protection for the interior of the building with the use of fast response sprinklers. In addition, protection from exterior exposure will be addressed through the provision of a dry deluge water system for the exterior side walls of the building. This system will be activated by linear heat detectors situated at the floor assemblies above the first and second storeys. Further, as noted above, the building will also be equipped with a fire alarm system which would not be required by the Code. 3. Dispute The issue at dispute between the Applicant and Respondent is whether the proposed measures, offered to compensate for the use of combustible construction in a building containing Group A, Division 2 and Group D occupancies and having exposing building faces containing unprotected openings of less than 10% of the exposing building face, provide sufficiency of compliance with Article and Sentence (1) of the Ontario Building Code (OBC). Article provides that a building classified as having a Group A, Division 2 occupancy is permitted to conform to the provisions of Sentence (2) if the building is sprinklered and not more than six storeys in building height. Sentence (2) requires that the building be comprised of noncombustible construction and that floor assemblies be fire separations having a fire-resistance rating of at least one hour. Furthermore, mezzanines are also to be provided with a one hour fire-resistance rating and all loadbearing walls, columns and arches are to have a fire-resistance rating at least equal to the supported assembly. In regard to the construction requirements of the exposing building face, Sentence (1) requires

3 -3- that, with exceptions not applicable here, where the prescribed limiting distance for a Group A, B, C, D or F3 occupancy permits the building face to include unprotected openings of no more than 10%, the exposing building face is to be of noncombustible construction having a fire-resistance rating of not less than one hour. In addition, the building is to be clad with noncombustible construction. With respect to the subject building where the most restrictive construction requirements are associated with the proposed Group A, Division 2 occupancy, the Code would require the building to be constructed of noncombustible construction. Further, as noted in the requirements of Sentence (1), noncombustible construction and cladding would be required where the exposing building face contains unprotected openings of less than 10% of the exposing building face, as is the case in this building. To compensate for the use of combustible construction framing materials and stucco in the subject building the Applicant is proposing certain compensating measures. These measures include sprinklering the entire building area, where only sprinklering of the A2 portions of the building would be required. Further, a dry deluge water system is proposed for protection of the building exterior walls in addition to the inclusion of a monitored fire alarm system which would not be required in this instance. 4. Provisions of the Ontario Building Code Group A, Division 2, up to 6 Storeys, Any Area, Sprinklered (1) A building classified as Group A, Division 2, that is not limited by building area, is permitted to conform to Sentence (2) provided (a) except as permitted by Sentence (1), the building is sprinklered, and (b) it is not more than 6 storeys in building height. (2) Except as permitted by Article , the building referred to in Sentence (1) shall be of noncombustible construction, and (a) floor assemblies shall be fire separations with a fire-resistance rating not less than 1 h, (b) (c) mezzanines shall have a fire-resistance rating not less than 1 h, and all loadbearing walls, columns and arches shall have a fire-resistance rating not less than that required for the supported assembly Construction of Exposing Building Face (1) Except as permitted by Articles and , if a limiting distance shown in Table A. or Table C. for a Group A, B, C, D or Group F, Division 3 occupancy classification permits an exposing building face to have unprotected openings not more than 10% of the exposing building face, the exposing building face shall be (a) of noncombustible construction having a fire-resistance rating not less than 1 h, and (b) clad with noncombustible cladding. 5. Applicant s Position The Agent for the Applicant outlined the history of the construction of the subject building advising that it was originally designed as a Part 9 structure for use as two, three storey semi-detached dwellings.

4 -4- During the time the building was being constructed and after the wood framing had been completed and stucco had been applied to the exterior, a prospective purchaser advised that they wished to use the building to accommodate a restaurant on the ground floor and offices and meeting rooms on the upper levels. In this regard, a change of use was applied for which brought the construction under Part 3 of the Code which includes more restrictive requirements for wall and floor assemblies. The Agent advised that the situation was now such that, given the intended use, the structure would no longer comply with the Building Code requirements. The wall assembly would be required to provide a one hour fire-resistance rating and be clad in noncombustible construction. Unfortunately, as a result of the advanced stage of construction, these requirements could not be easily accommodated. To compensate for the use of combustible construction elements, the Agent advised that quick response sprinkler heads were to be installed throughout the building. He also stated that a fire alarm system, which would not be required by the Code was also offered. In respect to protection of the exterior of the structure, the Agent advised that a deluge water system would be installed at the eaves of the building and a one hour fire rating would be provided on the interior of the structure by the use of drywall. Linear heat detectors situated at the floor assemblies above the first and second floors would activate the deluge system and, he submitted, would provide an equivalent level of protection as a one hour fire-resistance rating on the exterior. In summation, the Agent advised that the compensating measures being proposed to address the use of combustible building materials will, in his opinion, achieve sufficiency of compliance with the requirements of the Building Code. 6. Respondent s Position The Respondent submitted that a permit for the construction of two residential units had been issued by the building department. This permit included the used of fully combustible construction as would be permitted in a Part 9 application. When approached about the change of use to accommodate A2 and D occupancies within the subject building, the issue of conformance with the Part 3 requirements for use of noncombustible construction became apparent. The Respondent acknowledged the measures proposed by the Applicant to compensate for the use of combustible material but stated that he continued to have a concern. He did not feel comfortable accepting an equivalency of the magnitude as was being proposed. In summation, the Respondent maintained that he was unable to accept the proposed compensation and was concerned with what would be a Part 3 use in a Part 9 building in the centre of the downtown area. A significant amount of wood was involved in the framing and enclosure of the structure and, as a result, he could not view the building as being Code compliant. 7. Commission Ruling It is the decision of the Building Code Commission that the compensating measures to be provided in the multiple occupancy building (A2 and D) having exposing building faces with unprotected openings less than 10% of the exposing building face and includes elements of combustible construction will provide sufficiency of compliance with Article and Sentence (1) of the Ontario Building Code at Thomas Street, Oakville, Ontario.

5 -5-8. Reasons i) Sprinklering of the entire building will exceed OBC requirements which would only mandate sprinklering of the first and second floors. In addition, quick response sprinkler heads are to be used which will further contribute to the effectiveness of the suppression system as a compensating measure. ii) iii) iv) A fire alarm system, which is not required by the Code, will be provided. A dry deluge water system is to be installed at the eaves of the building on both sides of the structure. This deluge system will be activated by linear heat detectors. The building contains no residential occupancy.

6 -6- Dated at Toronto this 1st day in the month of August in the year 2002 for application number Len King, Vice Chair John Guthrie Gary Burtch