Special Projects Award of Excellence
Morrison Hershfield
M
orrison Hershfield, in partnership with BC Housing and project sponsors, expanded the Building Envelope Thermal Bridging (BETB) Guide to include details applicable to all Canadian climates and energy codes and developed a first-of-its-kind online database. ThermalEnvelope.ca was developed for users to easily search for building envelope details, compare approaches to mitigate thermal bridges and calculate the overall thermal transmittance of opaque wall assemblies, roofs and floors. These tools can play an important supporting role in achieving net-zero design and implementation within the Canadian construction industry. An expanded resource The industry is now undergoing significant changes to improve the overall energy performance of buildings. The National Energy Code for Buildings (NECB) aims to achieve net-zero energy consumption for all new buildings in Canada by 2030. To reach this ambitious goal, the industry requires new tools to affordably design and build such high-performance buildings. Prior to the launch of the BETB 48
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Guide in 2014, the impact of thermal bridges was largely overlooked in practice, energy standards and energy calculations. Their impact is now clearer and comprehensive thermal bridging calculations are becoming a requirement in codes and standards across the country— including NECB 2017, BC Energy Step Code, Vancouver Building Bylaw (VBBL) and Toronto Green Standard (TGS) Version 3—as well as internationally. The BETB Guide has become an important resource for thermal bridging calculations. The expanded BETB Guide and new online database aim to transform the building market by facilitating the design and construction of more thermally efficient building envelopes. Migrating the expanded guide to a web-based platform has minimized the need for project-specific thermal simulations, making calculations less onerous in practice.
“Making all this data public will help a lot of people start at the right place and reduce the energy impact of a lot of buildings in Canada.” – Jury
The database at ThermalEnvelope.ca provides a streamlined, automated process to find more than 500 common building envelope assemblies and interface details, perform and review calculations, provide compliance documentation and collaborate with design teams. Users can search for and compare details using such criteria as construction type, insulation characteristics, proprietary systems and desired performance level. This new and expanded resource moves beyond climate and construction practice in British Columbia and is now applicable to all energy standards and climates in Canada. It also provides details applicable for net-zero or Passive House (PH) design, all of which is timely and necessary, given new and contemplated changes to energy efficiency requirements across the country, along with federal, provincial and territorial government commitments to reducing greenhouse gases (GHGs) under the Pan-Canadian Framework on Clean Growth and Climate Change. A global and national issue Buildings consume large amounts of electricity and natural gas. Designing and constructing energy-efficient buildings and improving conservation in existing buildings can lead to large reductions in energy consumption and related GHG emissions.
PHOTO COU RT E SY MOR R I S ON H E R S H F I E L D.
The Building Envelope Thermal Bridging Online Database
September/October 2021
2021-10-18 10:14 AM
