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BCC Ruling No. 00-28-760

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

AND IN THE MATTER OF Sentence and of Regulation 403, as amended by O. Reg. 22/98, 102/98, 122/98, 152/99, 278/99, 593/99, 597/99 and 205/00 (the "Ontario Building Code").

AND IN THE MATTER OF an application by Mr. Claudio Rabagliao, Turner Fleischer Inc., Toronto, Ontario, for the resolution of a dispute with Mr.John Wright, Chief Building Official, City of Markham, Ontario, to determine whether the proposed installation of a single fan unit providing 24 L/s exhaust on a continuous basis to serve a bathroom with two fixtures requiring ventilation provides sufficiency of compliance with Sentence of the Ontario Building Code at the Sunrise Assisted Living facility of Markham, Swansea Road, Markham, Ontario

Mr. Claudio Rabagliao
Turner Fleischer Inc.
Toronto, Ontario

Mr. John Wright
Chief Building Official
City of Markham

Dr. Kenneth Peaker, Chair
Mr. Robert De Berardis
Mr. Michael Steele

Toronto, Ontario

June 14th, 2000

June 14th, 2000

Mr. David Kaminker, President
Leipciger Kaminker Mitelman and Partners Inc.
North York, Ontario
Agent for the Applicant

Mr. George Chan
Mechanical Engineer
City of Markham
Designate for the Respondent


1. The Applicant

Mr. Claudio Rabagliao, Turner Fleischer Inc., Toronto, Ontario, has received a building permit under the Building Code Act, 1992 and is currently constructing a care facility known as the Sunrise Assisted Living facility of Markham located on Swansea Road, Markham, Ontario.

2. Description of Construction

The The Applicant is currently building a new care and treatment facility classified as having a Group B, Division 2 major occupancy. The structure is described as three storeys in building height, 1,891 m2 in building area and is of noncombustible construction. The building is equipped with a fire alarm system, a standpipe and hose system and a sprinkler system. A central kitchen and dining facility will be provided in the building for the residents.

The facility consists of a total of 81 suites, each with a separate bathroom. Each bathroom consists of a water closet, a lavatory and a bathtub. The bathrooms are ventilated to the roof by a central exhaust system which includes a heat recovery ventilator.

The suites are equipped with individual heat/cooling systems which can be controlled. As well, the windows may be opened.

The construction in dispute involves the exhaust ventilation in the suite washrooms. Each suite washroom has two fixtures that require ventilation. The Applicant is proposing that the suite washrooms be equipped with a single fan unit that provides 24 L/s of exhaust on a continuous basis. The exhaust would then be vented to a heat recovery system which preheats the fresh air supply ventilation. The design of the system is intended to provide continuous ventilation consisting of supply and exhaust air in each suite.

3. Dispute

The issue at dispute between the Applicant and Respondent is whether the proposed installation of a single fan unit providing 24 L/s exhaust on a continuous basis, which serves a washroom with two fixtures requiring ventilation, provides sufficiency of compliance with Sentence of the Ontario Building Code. This provision requires that the exhaust capacity for each sanitary fixture, excluding wash basins, within a bathroom must be at least 24 L/s (50 cfm). Therefore, for washrooms with two fixtures requiring ventilation as is the case in the subject building, the required level of ventilation is 48 L/s (100 cfm).

As noted, the Applicant is proposing to provide fan units that offer only 24 L/s of exhaust. The system, as proposed however, operates on a continuous basis and not intermittently, i.e., only when in use. The OBC, however, does not contain provisions which

4. Provisions of the Ontario Building Code

Sentence Governing Documents

(1) In the case of a conflict between the provision of this Code and those of a referenced document, the provision of this Code shall govern.

Sentence Exhaust Ducts and Outlets

(12) Except for wash basins (lavatories), the exhaust air provided shall not be less than 24 L/s (50 cfm) for each sanitary fixture listed in Sentence (8).

5. Applicant's Position

At the outset, the Agent for the Applicant stated that the subject building is based on an assisted living concept, but has the appearance of a regular residence. He further noted that the building was designed by a US architectural firm. Likewise, the ventilation system has been designed by a mechanical engineer from the US.

The Agent outlined that the proposed design of the single fan unit provides 24 L/s for the washroom and that the exhaust is continuous. He further added that the exhaust is connected to a heat recovery system which preheats the fresh air supply and that the proposed ventilation system relies on a concept of a continuous ventilation of supply and exhaust air in each suite.

The Agent stated that the exhaust system provided is a superior system to the minimum intermittent system accepted by the Code. He argued that if 48 L/s of intermittent exhaust satisfies Code requirements, then 24 L/s of continuous exhaust should at least be considered equivalent to Code. The Agent acknowledged that the proposed washroom ventilation system does not comply with the prescriptive requirements of Sentence Nevertheless, he maintained that the proposal meets the intent of this provision.

As the Agent argued, an intermittent system that operates probably only one hour per day would exhaust roughly 6,000 ft3 whereas a continuously running ventilation system would output 72,000 ft3, a 12-fold increase in air quality. Moreover, since the suites are private with nearly all having a single occupant the washroom fixtures would therefore tend not to be used simultaneously. As well, the Agent felt that the ventilation requirement for each fixture seemed onerous and questioned the additional exhaust capacity which would merely consume more energy.

The Agent referenced the ASHRAE 62-1989 Standard and the CAN/CSA-F326-M91 Standard, both of which provide for intermittent or continuously operated single fan units. The ASHRAE 62- 1989 Standard is generally accepted across North America and distinguishes between ventilation for public washrooms and residential washrooms. Its requirement for residential washrooms is 24 L/s for intermittent operation, or 10 L/s for continuous operation. He noted that the ASHRAE Standard does not specify an exhaust quantity per fixture for a residential washroom, as it is presumed that only one fixture is operated at one given time. The level of ventilation required in the CAN/CSA-F326-M91 Residential System Ventilation Code is almost exactly the same, the Agent added.

Lastly, the Agent concluded that the ventilation design proposal is reasonable and represents good engineering practice. In his view, the Respondent was interpreting the Code in an excessively rigid manner. While there are obviously two fixtures requiring ventilation, the Agent felt it important that the Code be interpreted consistent with an understanding of engineering principles. If only one fixture is used at a time, coupled with continuous ventilation, then that should be considered sufficient and thus meet Code requirements.

6. Respondent's Position

The Designate for the Respondent submitted that the OBC is very clear on the issue in dispute and that no interpretation is needed. In the context of the subject building, Sentence requires that each bathroom containing a water closet and shower must have an exhaust capacity of not less than 48 L/s (2 x 24 L/s for each sanitary fixture). In addition, the OBC does not provide an alternate option for the exhaust capacity for a fan which operates on a continuous basis.

Nevertheless, the Designate did concede, however, that he thought the proposal had some merit. He commended the HRV on the washroom exhaust and acknowledged that the ASHRAE 62-1989 Standard for the continuous exhaust allows for a reduction of ventilation to only 24 L/s for each bathroom.

However, the Designate noted that Sentence of the OBC stipulates that where there is a conflict between the provisions of the OBC and the provisions of a document referenced by the Code, the "provision of this Code shall govern". Thus the Designate felt compelled to uphold Ontario Building Code requirements and concluded by indicating that each bathroom must have a minium of 48 L/s (100 cfm) exhaust as required by

7. Commission Ruling

It is the decision of the Building Code Commission that the proposed installation of a single fan unit providing 24 L/s exhaust on a continuous basis to serve a bathroom with two fixtures requiring ventilation provides sufficiency of compliance with Sentence of the Ontario Building Code at Sunrise Assisted Living facility of Markham, Swansea Road, Markham, Ontario.

8. Reasons

The overall level of safety in the building has been improved through the following factors:

  1. The building incorporates a ventilation system that provides for good air quality and includes energy conservation measures.

  1. A central continuous exhaust system is provided incorporating a heat recovery system.

  1. Since the suite washrooms are private facilities where only one fixture will likely be used at a time, continuous exhaust at 24 L/s may be used in this instance.

  1. The continuous exhaust system will provide for greater air change than normally required.

  1. The ventilation system design conforms to ASHRAE 62-1989 and CAN/CSA F326-M91.

  1. Suite windows are openable.

  1. A separate heat/cooling system is available in each suite.

  1. The central kitchen and dining facility within the building reduces the need to utilize individual cooking appliances within the suites.

Dated at Toronto this 14th, day in the month of June in the year 2000 for application number 2000-24.


Dr. Kenneth Peaker, Chair


Mr. Michael Steele


Mr. Robert De Berardis