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 of Regulation 403, as amended, (the Building Code). AND IN THE MATTER OF an application by Dan Einwechter, Challenger Motor Freight Inc., to determine whether the lower floor of the subject building qualifies as a ground floor when considering the definitions for grade and first storey as specified in Article of the Building Code at Challenger Motor Freight, 300 Maple Grove Road, City of Cambridge, Ontario. APPLICANT RESPONDENT PANEL PLACE Dan Einwechter Challenger Motor Freight Inc. Cambridge, Ontario Larry Simonato Chief Building Official City of Cambridge Tony Chow, Chair Susan Friedrich Gary Burtch Toronto, Ontario DATE OF HEARING February 17, 2005 DATE OF RULING February 17, 2005 APPEARANCES Robert Dyck Robert Dyck Architect & Engineer Inc. Kitchener, Ontario Agent for the Applicant Hardy Bromberg Deputy Chief Building Official City of Cambridge Designate for the Respondent

2 - 2 - RULING 1. Particulars of Dispute The Applicant has received a permit under the Building Code Act, 1992, and is constructing an office building at Challenger Motor Freight, 300 Maple Grove Road, Cambridge, Ontario. The subject building is a Group D office building, having a building area of 2,351 m 2. The building is comprised of non-combustible construction and is equipped with a sprinkler and fire alarm system. The construction in dispute involves the determination of the height of the building, specifically, whether the lowest level of the building can be considered the basement as opposed to the first storey. The dispute has arisen as a result of differing interpretations regarding the calculation of grade, which will then dictate whether a basement is present. If a basement is present then the floor assembly above the basement would be required to provide a minimum 45 minute fire resistance rating. The Applicant is basing his calculations for grade on the area of the footprint of the lowest level of the building. Two sides of this level are situated above grade, while the other two sides are underground with approximately 4 m above the finished floor. The issue with respect to grade calculation results from the fact that the second level of the building extends beyond the footprint of the lowest level. If calculating grade based on the footprint of the building on the ground level (above the first level), the calculation would result in the lowest level being considered a basement. 2. Provisions of the Building Code in Dispute Defined Terms (1) The words and terms in italics in this Code have the following meaning for the purposes of this Code, and where indicated, the following meaning for the purposes of the Act as well. First storey means the storey with its floor closest to grade and having its ceiling more than 1.8 m above grade. Grade means the average level of proposed or finished ground adjoining a building at all exterior walls. 3. Applicant s Position The Agent for the Applicant submitted that subject structure is a Group D office building, having a building area of 2,351 m 2 and a height of 3 storeys. He also submitted that the lowest level of the building has a smaller footprint than the second and third levels, which extend beyond the lower level at ground level. It is the determination of the average grade based on the exterior walls, which has precipitated this dispute and brought the parties to the Commission. In the application submitted, the Agent contended that the average grade should be calculated using the perimeter of the lowest level of the building. Using this approach, as is detailed in the average grade calculation submitted by the Agent, the average grade was calculated to be m. It was submitted that the ceiling of the lowest level is m below the finish floor level of

3 - 3 - the upper floor. Carrying this theory through to its conclusion, in order for the lowest level to qualify as the first storey, its ceiling is required to be 1.8 m above the adjoining average grade. The average grade, using the Agent s calculation approach, was determined to be m m minus m (for the ceiling of the lowest level) equals m, which is more than the requirement of 1.8 m. The Agent maintained that the lowest level therefore qualifies as the first storey of the subject building and, there would be no requirement to construct the floor assembly over the lowest level as a fire separation with a 45 minute fire resistance rating. The Agent presented a diagram of the subject building which detailed the layout and the grade plan. He drew attention to the fact that the lowest level of the building is approximately 930 m 2 while the next level up is approximately 2,323 m 2. He explained how he had determined the average grade using the perimeter of the lowest level and based on that calculation, he concluded that the subject building should be considered a 3 storey building. The Agent stated that the real concern is the spread of fire from the lowest level to the level above. He speculated that the grade could have been lowered around the building in order to have the numbers work for the determination of average grade but contends that this would not make the building any safer. The Agent described the occupancy of the lowest level as being offices, meeting rooms and a cafeteria. He added that there are a number of means of egress directly to the outside from this level. He explained the reason for not wanting to provide the floor assembly with a rated fire separation is that the owner wants the look of open ceilings and open steel joists in this building. The Agent suggested that the building should be considered a 3 storey building, and therefore the fire separation would not be required to have a 45 minute rating but rather the separation could be unrated. He noted that the building is fully sprinklered. In summation, the Agent reiterated that they could adjust the grade around the building such that the lowest level could be considered the first storey, but he stressed that this would not make the building any safer. He went to say that there are many access points for the Fire Department and that two of the four walls are completely exposed. He asked the Commission to look favourably upon their proposal. 4. Respondent s Position The Designate for the Respondent submitted that the subject structure is a Group D office building, having a building area of 2,351 m 2 and a height of two storeys. The Designate submitted that, based on his calculations, the building, in his opinion, is two storeys with a basement and therefore, the floor assembly above the lowest level is required to have a minimum 45 minute rated fire separation. The Designate submitted that based on his calculations, the average grade around the perimeter of the building area was determined to be m and the elevation of the lower level ceiling was determined to be m. This means the average grade, as measured around the building area is 1.21 m below the ceiling of the lower level. Therefore, it is the opinion of the Designate that the subject building is considered a two storey building with a basement. The Designate stated that the average grade should be calculated using the finished ground adjoining a building at all exterior walls. As such, the calculation of average grade, according to the Designate, should be determined using the entire building exterior which is adjacent to grade. It is the opinion of the Designate that using this approach for calculating average grade, the subject building is considered a two storey building with basement.

4 - 4 - The Designate concluded by reiterating that the lowest level of the subject building, in his view, is considered a basement that should be subject to the applicable construction requirements for a basement, including the requirement of a 45 minute rated fire separation for the floor assembly above. 5. Commission Ruling It is the Decision of the Building Code Commission that the lowest floor of the subject building does not qualify as the first storey when considering the definitions for grade and first storey as specified in Article of the Building Code at Challenger Motor Freight, 300 Maple Grove Road, Cambridge, Ontario. 6. Reasons i) Grade is calculated based on the average level of proposed or finished ground adjoining the building at all exterior walls and establishes the second level of this building as the first storey.

5 - 5 - Dated at Toronto this 17 day in the month of February in the year 2005 for application number Tony Chow, Chair Susan Friedrich Gary Burtch