Citation : Szuberwood v. Johnston 2022 ONBCC 03
Ruling No.: 22-03-1595
Application No.: B-2021-19
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 Sentence 3.2.3.1.(1) and Table 3.2.3.1.D. of Division B of Regulation 332/12, as amended, (the “Building Code”).
AND IN THE MATTER OF an application by Brian C. Szuberwood for the resolution of a dispute with William Johnston, Chief Building Official, to determine whether the alternative solution to install close-spaced sprinklers on the interior side of the unprotected openings that exceed those permitted by Table 3.2.3.1.D. in a 13-storey Group A, Division 2, Group D and Group F, Division 3 building, provides sufficiency of compliance with Sentence 3.2.3.1.(1) of Division B of the Building Code at the University of Toronto, 112 College Street, Toronto, Ontario.
APPLICANT Brian C. Szuberwood
Interim Executive Director, Capital Projects
University Planning, Design & Construction Operations &
Real Estate Partnerships
University of Toronto
Toronto Ontario
RESPONDENT William Johnston
Chief Building Official
City of Toronto
Toronto, Ontario
PANEL Stephen Wong, Chair
Matthew Graham
Alexandra Chow
PLACE via video conference
DATES OF HEARING January 27, 2022
February 1, 2022
DATE OF RULING February 6, 2022
APPEARANCES Brian C. Szuberwood
Interim Executive Director, Capital Projects
University Planning, Design & Construction Operations &
Real Estate Partnerships
University of Toronto
Toronto, Ontario
The Applicant
Troy Drummond
Principal, Senior Building Code Consultant
LMDG Building Code Consultants Ltd.
Toronto, Ontario
Agent for the Applicant
Richard Lai, P.Eng
Principal
Teeple Architects
Toronto, Ontario
Agent for the Applicant
Erin McClintock
Principal, Senior Building Code Consultant
LMDG Building Code Consultants Ltd.
Agent for the Applicant
Selva Panchanatham
Manager, Plan Review
City of Toronto
Toronto, Ontario
Designate for the Respondent
David Johnson
Building Code Examiner
City of Toronto
Toronto, Ontario
Designate for the Respondent
Victor Fan
Building Engineer
City of Toronto
Toronto, Ontario
Designate for the Respondent
RULING
1. Particulars of Dispute
The Applicant applied for a building permit under the Building Code Act, 1992, to construct a 13-storey Group A, Division 2, Group D and Group F, Division 3 building, at the University of Toronto, at 112 College Street, Toronto, Ontario.
The subject building is a new 13-storey building having one below grade parking level with a building area of approximately 2,045 m2. The building is classified as Group A, Division 2 (Assembly – Non-Residential College), Group D (Office), and Group F, Division 3 (Parking Garage), which also includes subsidiary storage and building services spaces. The building is of noncombustible construction, is equipped with a standpipe and hose system and is a fully sprinklered high building. The building is also equipped with a 2-stage fire alarm system.
The building is designed such that the exterior walls slope, creating an increasingly smaller floor plate ascending the building. The north exposing building face is located approximately 0.7 m (Ground Level) to 5.6 m (Level 13) from the adjacent property line. The east exposing building face is located approximately 0.5 m (Ground Level) to 3.8 m (Level 13) from the adjacent property line and the west exposing building face is located approximately 4.2 m (Ground Level) to 7.5 m (Level 13) from the adjacent property line.
The fire compartments for the building from Level 2 through Level 9 at the north, east and west exposing building faces are proposed to have more than the maximum permitted percentage of unprotected openings based on the available limiting distance, as determined in accordance with Sentence 3.2.3.1.(1) and Table 3.2.3.1.D.
Based on the above, close-spaced sprinkler protection (water curtain) located on the interior side of the permitted unprotected openings, as determined in accordance with Table 3.2.3.1.D. is proposed, and also on the interior side of the additional unprotected openings that exceed those permitted by Table 3.2.3.1.D. As such, all openings on the 3 building faces will be provided with close-spaced sprinkler protection. The function of the close-spaced sprinkler protection is to reduce the temperature and radiative heat through the openings as a means to limit fire spread between buildings. The remainder of the exterior walls will be provided with the required fire-resistance rating in accordance with Sentence 3.2.3.7.(1) and Table 3.2.3.7.
The dispute before the Commission centers on whether the alternative solution proposal to install close-spaced sprinklers on the interior side of the unprotected openings that exceed those permitted by Table 3.2.3.1.D. in the subject building provides sufficiency of compliance with Sentence 3.2.3.1.(1) of Division B of the Building Code.
2. Provisions of the Building Code in Dispute
3.2.3.1. Limiting Distance and Area of Unprotected Openings
(1) Except as permitted by Articles 3.2.3.10. to 3.2.3.12., the area of unprotected openings in an exposing building face for the applicable limiting distance shall be not more than the value determined in accordance with, (a) Table 3.2.3.1.B. or Table 3.2.3.1.C. for an exposing building face conforming to Article 3.2.3.2. of a building or fire compartment that is not sprinklered, or (b) Table 3.2.3.1.D. or Table 3.2.3.1.E. for an exposing building face conforming to Article 3.2.3.2. of a sprinklered fire compartment that is part of a building that is sprinklered in conformance with Section 3.2.
Table 3.2.3.1.D. Unprotected Opening Limits for a Building or Fire Compartment that is Sprinklered
Forming Part of Article 3.2.3.1.
Item
Exposing Building Face
Area of Unprotected Opening for Groups A, B, C, D and F, Division 3 Occupancies, %
Maximum Area, m2
Limiting Distance, m
0
1.2
1.5
2
2.5
3
4
5
6
7
8
9
1,
10
0
16
24
42
66
100
15
0
16
20
34
50
74
100
20
0
16
20
30
42
60
100
25
0
16
18
26
38
52
90
100
30
0
14
18
24
34
46
78
100
40
0
14
16
22
30
40
64
96
100
50
0
14
16
20
28
36
56
82
100
60
0
14
16
20
26
32
50
72
98
100
80
0
14
16
18
22
28
42
58
80
100
100
0
14
16
18
22
26
36
50
68
88
100
150 or more
0
14
14
16
20
22
30
40
52
66
82
100
3. Applicant’s Position
The Agent for the Applicant (“the Agent”) clarified that the dispute before the Commission is only in regard to the north, west, and east building faces for Level 2 to 9. Above the 9th level, the limiting distance complies with Table 3.2.3.1.D. in the Building Code.
The Agent indicated that given the sloped nature of the exterior glazed openings, compliance with the applicable acceptable solutions in Division B of the Building Code was deemed not attainable. Various options for prescriptive compliance were explored while still maintaining the additional glazed openings, specifically compliance with Article 3.2.3.7. by providing a sprinkler protected glazed wall assembly constructed in accordance with Article 3.1.8.18., proprietary rated glazing in compliance with Article 3.1.7.1. or closures constructed in accordance with Article 3.1.8.4. (i.e., Firelite, fire shutters, etc.). The Agent clarified that these options are not specifically approved to be installed in a sloped orientation. The Agent submitted that though glass block or wired glass installed in compliance with Article 3.1.8.14. is an acceptable solution, where the limiting distance is 1.2 m or greater, neither material was found to be feasible for this application.
The Agent explained that on Level 1 of the building there are no unprotected openings that are proposed too close to property line. The Agent reported that the south part of the building faces College Street and that, located next to the proposed building, there is a park which is owned by the Government of Ontario. To the north is another Government of Ontario building named the Frost Building. The Agent further submitted that there is no opportunity to enter into a limiting distance agreement.
To the east of the proposed building, there is another University of Toronto building named the Banting Building. This is a property to be renovated and redeveloped to connect to the subject proposed building. In three to five years, the property will be redeveloped. The Agent submitted that in the future, the fire protection for unprotected openings being proposed will be redundant as the building will be brought into compliance by connection to a building on the adjoining property. However, the issue of limiting distance to the north and west building faces will remain and require resolution.
To address this issue, an alternative solution was submitted but was rejected by the City of Toronto. The alternative solution proposes a water curtain on the interior side of the building, which would protect both the permitted unprotected openings and the additional unprotected openings. The Agent submitted that the alternative solution is intended to comply with Table 3.2.3.1.D. of the Building Code.
The Agent indicated that the alternative solution proposes corrective values for the values in Table 3.2.3.1.D., based on calculations which take into account the protection offered by the proposed water curtain for the glazed openings. The Agent submitted that the proposed design would protect 100% of the permitted and unpermitted unprotected openings for each fire compartment.
The Agent submitted that the alternative solution is proposing close-spaced sprinklers at 1.8 m apart. Where windows are less than 1.8 m in width, a single sprinkler is installed for these windows in accordance with NFPA 13, “Standard for the Installation of Sprinkler Systems.”
The Agent maintained that a water curtain created by automatic sprinklers has been found to effectively reduce the transfer of radiant heat through the water spray. In addition, water curtain sprinklers are intended to detect and control a fire near the opening and create a water curtain between the opening and the source of the fire.
The Agent presented finding from a research paper dated1960 by A.J.M. Heselden and P.L. Hinkley of the British Joint Fire Research Organization entitled "Measurement of the Transmission of Radiation Through Water Sprays". The paper concluded that a water curtain produced from water flows comparable with those of sprinkler installations can reduce radiation transmission by as much as 70%. Based on the above-noted design of the water curtain sprinkler system, and on the results documented in the technical paper, the Agent submitted that the transmission of potential heat radiation through the exposing openings will be reduced by at least 50%.
Subsection 3.2.3 of the Building Code requires that buildings be spatially separated. The intent of the requirement is to inhibit the spread of fire from one building to another. The Agent submitted that a sprinkler water curtain, provided by closely-spaced sprinklers, creates a barrier to limit or prevent the spread of flames from an opening.
In response to questions, the Agent submitted that close-space sprinkler system will be equipped with listed products, designed by a professional engineer, and will comply with NFPA 13. The Agent acknowledged that NFPA 13 does not have installation requirements for close-spaced sprinklers in a water curtain application for protecting unprotected openings in an exposing building face.
In response to questions the Agent submitted the assumption of all the calculations is that the glazing has failed and fallen away.
The Agent submitted that the proposed alternative solution conforms to Sentence 2.1.1.2.(1), Division C of the Building Code which states, “…Where no published test method to establish the suitability of an alternative solution proposed under Article 2.1.1.1. exists, then the tests used for the purposes of that Article shall be designed to simulate or exceed anticipated service conditions or shall be designed to compare the performance of the material or system with a similar material or system that is known to be acceptable....”.
In response to questions, the Agent acknowledged that not all tests were written for the purpose as stated in Sentence 2.1.1.2.(1) of Division C of the Building Code but claimed that the tests would simulate the anticipated service conditions and are used to derive the equations used for the alternative solution design.
The Agent stated that the proposed alternative solution initially included three research tests. However, the City of Toronto expressed concern about the age of the tests. As a result, the Applicant responded with a 4th research test conducted by Carlton University, with a more recent date of 2016. The research test reports are as follows:
- "Measurement of the Transmission of Radiation Through Water Sprays", J.M. Heselden and P.L. Hinkley of the British Joint Fire Research Organization, 1960:
Report concludes that water curtain can reduce transmission of radiation by 70%.
"Fire Tests of Stairwell-Sprinkler Systems", April 1981, L.Y. Cooper and J.G. O'Neil
“Sprinkler Protection of Exterior Glazing”, A. Kim, B. C. Taber, and G. D. Lougheed, Fire Technology, Vol. 34, No. 2, 1998
“Investigation into the use of a water curtain over openings to prevent fire spread”, Matt Turco, Paul Lhotsky and George Hadjisophocleous, Carlton University, 2016
The Agent submitted that the noted research tests concluded that a water curtain reduces heat flux to the target wall and therefore, allows a reduction in building distance from property line.
In response to questions the Agent submitted that they had contacted National Research Council (NRC) to conduct a full-scale test. However, NRC was not equipped to test the slope, size, orientation of sprinkler head, and flow rate as designed.
In response to questions, the Agent submitted that there is no installation standard. The alternative solution is not using a product complying with CAN/ULC-S101, “Fire Endurance Tests of Building Construction and Materials”.
The Agent submitted that the sprinklers protecting the glazed wall assembly will not be constructed in accordance with the requirements of ULC/ORD C263.1, “Sprinkler-Protected Windows Systems,” as per Article 3.1.8.18. Sprinkler Protected Glazed Wall Assembly. This testing standard is for vertical glazing windows. The proposed close-spaced sprinkler system will be installed in accordance with NFPA 13.
In response to questions, the Agent submitted that the formulas used for the alternative solution are not the same formulas from which the Building Code Table are derived. The Agent clarified that one formula comes from the Society of Fire Protection Engineering Handbook.
The Agent submitted that the proposed system will achieve a level of performance for a specified time as per Table 3.2.3.7. Minimum Construction Requirements for Exposing Building Faces and argued that the proposed close-spaced sprinkler water curtain system will produce heat flux reduction that will achieve the equivalent performance of a 1 hour fire-resistance rating for exposing building face wall assemblies with a reliability rate of 92%.
The Agent submitted that after the refusal by the City of Toronto and at the request of University of Toronto, the alternative solution proposal went through a Peer Review process. The Peer Review report concluded that the alternative solution meets level of performance requirement to limit spread of fire between buildings.
The Agent clarified that the purpose of the alternative solution is not to provide a fire-resistance rating but to attenuate heat, which is the purpose of Subsection 3.2.3. of the building code.
In summary, the Agent submitted that the proposed alternative solution complies with Table 3.2.3.1.D. by using close-spaced sprinklers to calculate corrective values for allowable unprotected openings. The Agent concluded the design complies with the values in Table 3.2.3.1.D. and the performance level established by Subsection 3.2.3. of the Building Code.
4. Respondent’s Position
The Designate for the Respondent (“the Designate”) submitted that the Applicant’s alternative solution proposal is to install close-spaced sprinkler protection on the interior side of sloped exterior glazed openings in lieu of fire rated exterior wall assemblies or fire protection rated closures where the percentage of unprotected openings exceeds the maximums permitted in Table 3.2.3.1.D. Further, in some locations the unprotected openings proposed exceed those permitted in Table 3.2.3.1.D. by 100%.
The Designate advised that a limiting distance agreement with adjacent landowners to permit the measurement of the limiting distance beyond a property line was not secured.
The Designate submitted that the alternative solution does not demonstrate that close-spaced sprinklers can achieve an equivalent fire-resistance rating as required by Article 3.2.3.7. for exposing building face wall construction. Therefore, the alternative solution does not demonstrate it can achieve an equivalent fire-resistance rating as required by Articles 3.2.3.1. and 3.2.3.7.
The Designate contended that NFPA 13 does not mention that fire-resistance ratings can be achieved by using close-spaced sprinklers. NFPA 13 does not specify an equivalent fire separation rating for water curtains installed in accordance with Paragraph 8.15.4.1 and designed in accordance with Subsection 11.3.3 nor does it address close-spaced sprinklers for exposure purposes (refer to item 9 of NFPA 13-2016 FAQ's).
Further, the Designate submitted that NFPA 13 has installation requirements for close-spaced sprinklers for vertical openings. In this case, the openings are sloped. The alternative solution references water curtain research tests to support their proposal. However, the experimental setup for one of the tests used a wall that was 4 m high with a single small opening of 2 m wide and 1.5 m high. This is significantly different than the design proposed where the opening height is 3.6 m and width is also much larger. In addition, the sprinkler location in one of the referenced research tests is installed outside of the fire compartment where the alternative solution proposes to install sprinklers inside the fire compartment.
Although in the Carleton University test submitted, the sprinklers are installed outside the fire compartment, the Designate submitted that the report clearly states that to ensure accurate results, further tests should be conducted and studied using different compartment separations and openings in differing configurations.
The Designate noted that in the "Measurement of the Transmission of Radiation Through Water Sprays" report submitted, the test setup had no compartmentation. The test did not have an exposed wall but instead used a radiant panel to simulate a fire. In this test, there was no fire and no compartmentation. In addition, the sprinkler location installed in the test was 4.3 m away, which is entirely different than the proposal.
The Designate submitted that the City of Toronto is not able to validate the formulas used in the alternative solution proposal. They are not aware of the steps used in obtaining the calculations and further, it is not known if the calculations and formulas used for the alternative solution were the same as those used in the Building Code.
The Designate explained that the City of Toronto reached out to various organizations including the National Fire Protection Association (NFPA) and were advised that NFPA had not looked at close-spaced sprinklers in this configuration. In addition, the Canadian Automatic Sprinkler Protection Association clearly states that NFPA 13 does not address this type of design at present.
The Designate contended that the Applicant has acknowledged the glazing will fail in a fire, which would allow fire to travel outwards and upwards like a chimney and spread the fire outdoors.
The Designate submitted that the parameters for sprinkler activation have not been validated. The close-spaced sprinklers in this case are not considered window sprinklers as they are located 610 mm (2 feet) away from the glazing. The test reports submitted have testing conditions that are significantly different than those in the alternative solution. For example, in the referenced 2016 test, the sprinkler system was installed outside of the fire compartment. In the subject proposal, the sprinkler is installed inside the fire compartment. In Carleton University’s test, the target wall face was getting wet. In the alternative solution, this will not be the case.
The Designate pointed out that testing results can be different depending on test setup and conditions. The "Investigation into the use of a water curtain over openings to prevent fire spread" report shows that the target wall radiant heat reduction is maximum 49%. However, in "Measurement of the Transmission of Radiation through Water Sprays" report, the target wall radiant heat reduction is up to 70%. Therefore, testing results can vary significantly based on testing conditions.
Further, the Designate submitted that the “Investigation into the use of a water curtain over openings to prevent fire spread” report suggests further tests should be conducted before the research results can be practically used for assessing the performance of a water curtain over a compartment opening.
In addition, the Designate raised concern about the activation of sprinklers and whether there is sufficiently high temperature to activate sprinklers as is expected should there be no glazing to confine heat. The Designate maintained that it is his opinion that the glazing must stay in place for sprinklers to be activated.
In summary, the Designate submitted that the percentage of unprotected openings, as outlined in the alternative solution, exceeds those permitted by Subsection 3.2.3., and the proposed closed-spaced sprinkler protection installation on the interior side of the sloped exterior glazed openings, in lieu of fire rated exterior wall assemblies or fire protection rated closures, exceed the maximum percentage of unprotected openings permitted by Table 3.2.3.1.D.
The Designate maintained that the proposed alternative solution does not sufficiently demonstrate compliance by using close-spaced sprinkler to achieve an equivalent fire-resistance rating in vertical exterior wall, as the testing data and results used in the proposed alternative solution have not been validated by a standard’s Council of Canada accredited testing organization.
5. Commission Ruling
It is the decision of the Building Code Commission that the proposed alternative solution to install close-spaced sprinklers on the interior side of the unprotected openings that exceed those permitted by Table 3.2.3.1.D. in a 13 storey, Group A, Division 2, Group D and Group F, Division 3 building, does not provide sufficiency of compliance with Sentence 3.2.3.1.(1) of Division B of the Building Code at the University of Toronto, 112 College Street, Toronto, Ontario.
6. Reasons
i) It is the Commission’s opinion that the Applicant’s approach for establishing heat flux reduction to increase permitted unprotected openings is theoretical analysis. The majority of the testing information provided to support the theoretical analysis was dated, and the test conditions and parameters were not similar or comparable to the anticipated building service conditions in the proposed alternative solution.
ii) Building condition specific testing was not provided for sloped glazing with a water curtain to demonstrate and verify the approach for heat flux reduction analysis in order to support the proposal to increase the percentage of permitted unprotected openings.
iii) The Applicant’s party provided examples of other buildings where close-spaced sprinklers had been used as an alternative solution to increase the percentage of permitted unprotected openings but was unable to demonstrate that those examples are similar or identical to the subject building design and further, whether acceptable performance under service conditions was achieved in those examples.
Dated at the City of Toronto this 6th day in the month of February in the year 2022 for application number B-2021-19.
Stephen Wong, Chair
Matthew Graham
Alexandra Chow