Division B
Acceptable Solutions

Part 5 — Environmental Separation

Section 5.3. Heat Transfer

(See Appendix A and Part 10.)
(See Appendix A.)

5.3.1. Thermal Resistance of Assemblies Required Resistance to Heat Transfer
(See Appendix A.)
1) Intent StatementExcept as provided in Sentence (2), where a building component or assembly will be subjected to an intended temperature differential, the component or assembly shall include materials to resist heat transfer or a means to dissipate transferred heat in accordance with the remainder of this Subsection.
2) Intent StatementThe installation of materials to resist heat transfer in accordance with the remainder of this Subsection is not required where it can be shown that uncontrolled heat transfer will not adversely affect any of
a) the health or safety of building users,
b) the intended use of the building, or
c) the operation of building services. Properties to Resist Heat Transfer or Dissipate Heat
(See Appendix A.)
1) Intent StatementTaking into account the conditions on either side of the environmental separator, materials and components installed to provide the required resistance to heat transfer or the means implemented to dissipate heat shall provide sufficient resistance or dissipation,
a) to minimize surface condensation on the warm side of the component or assembly,
b) in conjunction with other materials and components in the assembly, to minimize condensation within the component or assembly,
c) in conjunction with systems installed for space conditioning, to meet the interior design thermal conditions for the intended occupancy, and
d) to minimize ice damming on sloped roofs.
(See Appendix A.) Location and Installation of Materials Providing Thermal Resistance
1) Intent StatementWhere a material required by Article is intersected by a building assembly, 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) Intent StatementMaterials providing required thermal resistance shall have sufficient inherent resistance to airflow or be positioned in the assembly so as to prevent convective airflow through and around the material. (See Appendix A.)
3) Intent StatementSpray-in-place polyurethane insulation shall be installed in accordance with the requirements of CAN/ULC-S705.2, “Thermal Insulation – Spray-Applied Rigid Polyurethane Foam, Medium Density — Application.”