The Ontario Building Code | Construction Index and Hazard Index
11.2.1.1. Construction Index and Hazard Index
(1) Where proposedconstruction will result in the change of major occupancy of all or part of an existing building to another major occupancy, the building shall be classified as to its,
(a) construction on the basis of its construction index as provided for in this Part, including Table 11.2.1.1.A., and
(b) occupancyon the basis of its hazard index as provided for in this Part, including Tables 11.2.1.1.B. to 11.2.1.1.N.
(2) Small or medium sized existing buildings as determined in Tables 11.2.1.1.B. to 11.2.1.1.N. facing multiple streetsmay be assigned a hazard index credit of 1, which may be subtracted from the hazard index of the proposed major occupancy to reduce the additional upgrading required by Table 11.4.3.4.A. provided,
(a) the buildingdoes not contain a Group B, Division 1, a Group C, or a Group F, Division 1 occupancy, and
(b) firefighting access complying with Articles 3.2.5.1. to 3.2.5.5. or Subsection 9.10.20. is provided.
(3) The requirements of Articles 3.2.2.20. to 3.2.2.83. do not apply to this Part.
In Plain Language
The construction index and hazard index, tools used to evaluate an existing building's safety level relative to current requirements, are defined and described in this article.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.