BUILDING CODE COMMISSION

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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 , Clause (1)(c) and Sentence (1) of Regulation 403, as amended, (the Building Code). AND IN THE MATTER OF an application by Garry Fraser, TDL Group, to determine whether the proposed automated storage and retrieval system that serves as structural support for the building in addition to support for the racking system components provides sufficiency of compliance with Article , Clause (1)(c) and Sentence (1) of the Building Code at the Southgate Distribution Centre, 950 Southgate Road, Guelph, Ontario. APPLICANT RESPONDENT PANEL PLACE Garry Fraser TDL Group Oakville, Ontario Bruce Poole Chief Building Official City of Guelph Len King, Vice-Chair Ed Link John Guthrie Toronto, Ontario DATE OF HEARING February 3, 2005 DATE OF RULING February 3, 2005 APPEARANCES Les Muniak Larden Muniak Consulting Incorporated Toronto, Ontario Agent for the Applicant Jeremy Laur Plans Examiner City of Guelph Designate for the Respondent

2 - 2 - RULING 1. Particulars of Dispute The Applicant has applied for a permit under the Building Code Act, 1992, and is constructing an automated storage and retrieval system (ASRS) at the Southgate Distribution Centre, 950 Southgate Road, Guelph, Ontario. The proposed building will be 14,396 m 2 in building area and will have a Group F, Division 2 major occupancy classification. The structure is to be comprised of non-combustible construction and will be equipped with sprinkler, fire alarm and standpipe and hose systems. The proposed structure is described by the Applicant as a one storey warehouse facility having a Group F, Division 2 major occupancy classification. The subject of this hearing is the Automated Storage and Retrieval System (ASRS), which is approximately 30 m in height, 143 m in length and 18 m in width. The structure will be assembled on site and the structure will support its own walls and roof, as opposed to a typical ASRS, which is installed within a building as a selfcontained structural system. The subject ASRS as described by the Applicant is a high bay rack storage modular rack frame structure built on a mat slab foundation that is used to support the building envelope, pick levels, pallet storage locations, ventilation and/or refrigeration equipment, conveyors and automated cranes called SRMs (Storage and Retrieval Machines). A vestibule area between the Freezer ASRS and the Ambient ASRS is column-supported structure with box beam foundations. The rack frame structure consists of a system of vertical truss frames made of hollow structural section members. The rack frames are anchored to the mat slab and include cross ties and bracing to transfer loads between the frames. Siding panels and roof deck are fastened to girts supported from the rack frames. Pick levels are supported from the rack frames. Ventilation equipment installed in steel framing is supported from the rack frames. Refrigeration equipment, housed in penthouse enclosures, is installed on grating supported from the rack frames. Conveyors are supported from platforms that are supported from the rack frames. The cranes are supported from the mat slab and guided by rails from the mat slab at the bottom and from the cross ties at the top between the rack frames. One or more elevated levels are for personnel access to perform pallet pick operations. The pick levels may also support conveyors and other distribution equipment. Several issues are at dispute between the two parties, the first being the height of the structure, the Applicant maintains that the building should be considered to be one storey, while the Respondent believes the building to be between one and three storeys. Specifically, if each of the pick levels are considered to be storeys, then the Code would require these levels to be constructed in accordance with the floor fire separation requirements found in Section To compensate for compliance in this area, the Applicant is proposing to upgrade the sprinkler system to meet Factory Mutual Standards. Further, the travel distance from each pick level would be required to adhere to Clause (1)(c) and not exceed the maximum travel distance of 45 m. In lieu of the travel distance requirements, the Applicant has conducted a time based egress analysis. Additionally, Article (1) would require the exit stairs from the pick levels to be separated from the rest of the building by a fire separation. A further issue at dispute is the subject structure and the ASRS itself providing the structural frame support for the buildings exterior walls and roof as opposed to the typical ASRS where the system is installed within a building as a self contained structural system.

3 Provisions of the Building Code in Dispute Group F, Division 2, Any Height, Any Area, Sprinklered (1) Except as permitted by Articles to , a building classified as Group F, Division 2 shall conform to Sentence (2). (2) Except as permitted by Article , the building referred to in Sentence (1) shall be of noncombustible construction, and (a) (b) (c) (d) except as permitted by Sentence (1), the building shall be sprinklered, floor assemblies shall be fire separations with a fire-resistance rating not less than 2 h, mezzanines shall have a fire-resistance rating not less 1 h, and loadbearing walls, columns and arches shall have a fire-resistance rating not less than that required for the supported assembly. Clause (1)(c) Location of Exits (1) Except as permitted by Sentences (2), (3) and (6), if more than one exit is required from a floor area, the exits shall be located so that the travel distance to at least one exit shall be not more than (c) 45 m in a floor area that contains an occupancy other than a high hazard industrial occupancy, provided it is sprinklered, Sentence (1) Fire-Resistance Rating of Exit Separations (1) Except as permitted by Sentences (2), (4), (3), (2) and (1), 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 , but not less than 45 min, for (a) (b) the floor assembly above the storey, or the floor assembly below the storey, if there is no floor assembly above. 3. Applicant s Position The Agent for the Applicant submitted that the Building Code does not adequately address the uniqueness of the subject ASRS structure with respect to exiting requirements. It is his submission that a time-based egress analysis is more appropriate when evaluating exiting from the subject structure. The Agent further submitted that the installation of a sprinkler system, which has been increased in design to Factory Mutual standards, provides active fire protection instead of passive fire protection as is usually provided by spray on fireproofing. The Agent described the structure as being designed with pick levels and stated that the majority of the product stored within the system is loaded and unloaded by cranes, adding that there is only a narrow strip in the middle which is occupied by employees. He explained that the first level is accessed by employees and uses manned trucks to move the product. The second and third levels have a limited number of occupants, two per level in the ambient storage area and the freezer storage area. Above that point the system is unoccupied and fully automated. The Agent went on to say that in order to comply to the Code requirements the floor assembly and the structure would require a fire resistance rating of 2 hours. He explained that structure,

4 - 4 - including the storage racks, is fully sprinklered. He referred to Article of the Code which states, in part, A structure shall be protected against fire spread and collapse in conformance with good fire protection engineering practice. He elaborated on the design of the sprinkler system, which has been significantly enhanced, being designed and configured to both extinguish product fires and to wet and cool the steel supporting elements of the rack structures. He further explained that the racks have been structurally designed to withstand the weight of the products plus the discharge weight of the sprinkler water. In his opinion, the design of this active, sprinkler water based fire protection system, which has been tested to Factory Mutual standards, provides the equivalency of the Code s requirement of providing a 2-hour fire resistance rating. The Agent also stated that a fire alarm system would be installed, even though this is not a requirement. With respect to travel distance to an exit point, the Agent advised that exit points are provided at the centre and each end of the levels. He admitted that the travel distance is beyond the 45 m limit and uses open stairs as the means of egress. He informed the Commission that in lieu of meeting the required 45 m travel distance, they have instead used a time-based egress analysis in hopes of providing a sufficiency of compliance with Clause (1)(c) of the Code. The detailed findings of their analysis can be found in Appendix A of the Supporting Documentation report submitted by the Agent for the Applicant. In brief, the actual egress time from the most remote location within the ASRS to the outside of the building was calculated as being 1 minute, 16 seconds. Additionally, a very conservative pre-flow time of 3 minutes was added to account for any delay in egress, such as potential delay in becoming aware of an alarm or delay by an occupant in taking action in case of an emergency, this resulted in a worst case evacuation time of 4 minutes, 16 seconds. It is the Agent s belief that this recognized method meets with the objectives and time periods described in the Supplementary Guidelines of the Code and therefore provides sufficiency of compliance for exiting requirements. When questioned as to whether the structure would comply with the proposed amendment to the Code numbered , the Agent was able to confirm that it would comply with this amendment in all aspects with the exception of two. The structure is beyond the 24 m maximum height as stipulated in proposed amendment and it is not a self-contained structural system within a building. The Agent summed up by stating that it is his opinion the structure provides sufficiency of compliance. The occupancy of the facility is relatively low and the structure would comply with the proposed amendment in all but two aspects. The following compensating measures were offered, the building will be equipped with a fire alarm system and the sprinkler system will exceed the requirements of NFPA. 4. Respondent s Position The Designate began by saying that the City supports the Applicant in this concept. It is his opinion that Article of the Code could apply to the fire rating requirements but it would not apply to the exiting requirements. The Designate for the Respondent submitted that he had two concerns with respect to this particular ASRS. The first is that in a typical ASRS the storage systems are used within a building as a self-contained structural system while this building s proposed rack and storage system is not contained within a building but is the structural frame for supporting the building s exterior walls and roof. His second concern is with the height of the structure itself being approximately 30 m. He then explained that, in looking to proposed amendment number , he determined that this proposal could comply with these requirements except for the fact that the structure is not a

5 - 5 - rack and storage system within a building and that the building exceeds the height restriction. The Designate stated that he accepts the use the time-based egress analysis for most of the structure, however, they believed that this approach should not be applied to the ground floor. It was his belief that the ground floor level would still need to meet the 45 m requirement of the Code. The Designate would like to see this proposal meet all of the requirements contained in proposed amendment He made specific mention of the following requirements: draft stops at the opening of stairs, fire alarm system, and conveyor and lift gate requirements. He further stated that a sprinkler system would be required under each platform. The Designate then questioned the reliability of smoke alarms in the freezer area of the ASRS. The Agent responded that they have been investigating some new products and agreed to install an equivalent detection device in the freezer area. The Designate summed up by restating that he would expect this proposal to meet the requirements stipulated in proposed amendment Commission Ruling It is the Decision of the Building Code Commission that the proposed automated storage and retrieval system that serves as structural support for the building in addition to support for the racking system components provides sufficiency of compliance with Article , Clause (1)(c) and Sentences (1) and (1) of the Building Code at the Southgate Distribution Centre, 950 Southgate Road, Guelph, Ontario, on condition that: a) The proposed automated storage and retrieval system (ASRS) building is to comply in all respects with the proposed amendment to the Building Code numbered , with the following exceptions: i) The 24 m maximum height cited in proposed amendment may be exceeded in the proposed building by 6.48 m. ii) The ASRS and the building may be combined as opposed to being a selfcontained structural system within a building as described in the proposed amendment. b) Smoke detectors are to be installed under all solid decking and walkways as cited in proposed amendment with the exception of in the freezer area, where equivalent detection devices will be installed to the satisfaction of the Chief Building Official for the City of Guelph. c) A sprinkler system meeting Factory Mutual standards 2-8N and 8-9 is to be installed. In the ambient temperature area of the ASRS building, the system will have an in-rack sprinkler design density of 0.40 usgpm/ft 2 over 2,000 ft 2, increased to 0.45 usgpm/ft 2 over the 2,000 ft 2 where plastics are stored. In-rack sprinklers, in both the ambient ASRS and the freezer ASRS, will have a minimum flow of 30 usgpm/head. d) The building will be equipped with a fire alarm system installed in accordance with the requirement of the Building Code.

6 Reasons i) The proposed automated storage and retrieval system building would comply with proposed amendment, , in all respects except for the height requirement and the shelf and rack system is self- supporting as opposed to being a selfcontained structural system within a building as is described in the proposed amendment. ii) iii) iv) A complete fire alarm system is being provided. A sprinkler system meeting Factory Mutual standards, and exceeding the requirements of NFPA is being installed. The highest occupied floor of the building is 9 m above ground level. v) The facility will operate with relatively low occupancy with only two employees on each pick level. vi) A time based egress analysis has been conducted, resulting in an actual egress time from the most remote location within the ASRS to the outside of the building to be 1 minute 16 seconds. The worst case results, including a 3 minute pre-flow period before evacuation, results in a time of 4 minutes 16 seconds. The Commission is satisfied that the results of this analysis will provide sufficiency of compliance with the exiting requirements outlined in the Code.

7 - 7 - Dated at Toronto this 3rd day in the month of February in the year 2005 for application number Len King, Vice-Chair Ed Link John Guthrie