This study looks at the level of mould growth in wood-framed buildings constructed in coastal climates, particularly on the roof sheathing of ventilated attics. It includes those buildings that fully comply with code requirements without significant defects, and evaluates the factors that lead to moisture collection and mould growth in attics.
Managing uncertainty is core to all engineering analysis of building performance. Effective solutions are established when managing the risks associated with designs are balanced with the benefits to the clients and end users. Many engineering disciplines address uncertainty with statistical analysis, such as limit state design in structural engineering, where the probability of failure, loads, and other design parameters are stochastic variables.
While venting glazed spandrels is cited to be a benefit to control heat buildup, several instances of spontaneous glass breakage in spandrel insulated glazing units, attributed to thermal stress, have been reported in vented spandrel cavities used with an opacifier on the inside glass surface.
One of the defining characteristics of new high-rise residential apartment building design in Canada today is the thermally broken, open-back aluminum frame ‘window wall’ building envelope system. Until recently, Canadian building codes and Canadian and North American fenestration standards have not recognized window wall as a distinct cladding system.
Thermally efficient building envelopes have long been recognized as a necessity for low energy buildings in heating dominated climates. Low energy buildings are not only a goal for buildings built to green rating systems, but are also a stated long-term developmental objective of energy standards that are applicable to all large buildings.
The building sector is the largest consumer of energy in the United States and Canada – approximately 20 to 40% of primary energy use. Space conditioning makes up nearly half of energy use in residential buildngs (DOE, IEA, NRCAN). This reality creates a significant need for increased energy efficiency in buildings.
Morrison Hershfield developed a design protocol for the application of insulating sheathing to low-rise buildings with high interior relative humidity (maximum 60%) for a range of degree-day locations across Canada.
The reduced thermal resistance due to thermal bridging through steel and concrete framing can have a significant impact on the whole building energy performance. Uncertainty about the thermal performance of the building envelope can lead to inefficient design of HVAC systems, building operation inefficiencies, inadequate condensation resistance at intersections of components and compromised occupant comfort.
This guide aims to help the B.C. construction sector realize more energy-efficient buildings by looking at current obstacles and showing opportunities to improve building envelope thermal performance. Version 1.2 expands the thermal performance catalog with additional data for many newly analyzed assemblies and details.