The Ontario Building Code | Location and Installation of Materials Providing Thermal Resistance
5.3.1.3. Location and installation of Materials Providing Thermal Resistance
(1) Where a material required by Article 5.3.1.1. is intersected by a buildingassembly, penetrated by a high conductance component or interrupted by expansion, control or construction joints, and where condensation is likely to occur at these intersections, penetrations or interruptions, sufficient thermal resistance shall be provided so as to minimize condensation at these locations.
(2) Materials providing required thermal resistance shall have sufficient inherent resistance to air flow or be positioned in the assembly so as to prevent convective air flow through and around the material.
(3) Spray-in-place polyurethane insulationhttp://thehandyforce.com/insulation/" title ="Toronto home insulation">insulation shall be installed in accordance with the requirements of CAN/ulc-S705.2, "Thermal insulationhttp://thehandyforce.com/insulation/" title ="Toronto home insulation">insulation - Spray Applied Rigid Polyurethane Foam, Medium Density, Installer’s Responsibilities - Specification".
Section 5.4. Air Leakage
5.4.1. Air Barrier Systems
In Plain Language
Materials providing thermal resistance (insulation) must be located and installed correctly within an assembly, since improperly placed insulation can perform far worse than its rated value suggests.
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.