The role of the building envelope research team in this project was to assess whether midrise wood-frame (LWF) and cross-laminated timber (CLT) building envelope solutions developed by the fire research team to meet the fire provisions of the National Building Code (NBC) 2010 Part 3 Fire Protection, would also meet the NBC Part 5 Environmental Separation requirements relating to the protection of the building envelope from excessive moisture and water accumulation. As well, these wood-based mid-rise envelope solutions were to be assessed for their ability to meet Part 3 Building Envelope of the National Energy Code for Buildings (NECB) 2011. Requirements relating to heat, air, moisture, and precipitation (HAMP) control by the building envelope are included in Part 5 Environmental Separation of the NBC 2010. Part 5 addresses all building types and occupancies referred to in Part 3, but unlike requirements for fire protection, this section of the code was written more recently and is generic, including requirements that are more objective-oriented rather than prescriptive requirements pegged to specific constructions systems. The investigated methodologies developed and adapted for this study took those code characteristics into account.
To evaluate the building envelope performance of the generic exterior wall assemblies developed for use in mid-rise wood buildings, hygrothermal properties of materials used in the assemblies are needed as input data for hygrothermal modelling. Hygrothermal properties were developed for fire retardant treated plywood, regular gypsum sheathing, spray polyurethane foam and cross-laminated timber. This report documents results of the hygrothermal property determinations.
The objective of this part of the research project was to generate a set of reliable and
representative data on hygrothermal properties of a number of selected building materials as
1. D-Blaze Treated Plywood
2. Dricon Treated Plywood
3. Gypsum Sheathing
4. Closed Cell Spray Polyurethane Foam Insulation (Purple in Colour)