How to Install Windows and Meet Demanding Thermal Code Requirements

11:20 a.m. – 12:20pm

John Straube, PhD, PEng

Knowledge Level: Intermediate
Credits: This session has been approved for 1.0 IIBEC CEH. | This session has been approved for 1.0 AIA LU/Elective. | 1 hour (60 min) of Education is eligible for 1 BSS Credit | 1 OAA Core Learning Hour | Session may qualify for PEEK CPD.
Session Topics(s): Exterior Wall: EW, Fenestration/Glazing: FG

Learning Objectives
At the end of this session, the attendee will be able to:

• Explain how building codes are changing to require improved thermal performance by reducing thermal bridges.
• Identify how the fundamental control layers maintain their continuity at the head and sill of typical windows.
• Describe the limitations of common window buck solutions for window installation 
• Identify how some newly available thermally improved materials and products can be used to make window installation thermally efficient as well as air- and water-tight.

Description
The building enclosure industry has been moving to the use of exterior continuous insulation for decades, and the thickness of the insulation required has steadily been increasing. Thicker exterior insulation requires new design solutions for cladding attachment and penetrations, such as window openings. Modern emerging building codes, such as the National Energy Code for Buildings 2020 in Canada and ASHRAE 90.1-2022 Energy Standard for Sites and Buildings Except Low-Rise Residential Buildings, require the not-inconsiderable thermal bridging impact of window installation details to be considered. Finally, the need to focus on the water and airtightness of window installations is now widespread. New standards, such as CSA A440.6, High Exposure Fenestration Installation, provide requirements for demanding applications. This session will review design and construction challenges of window installation in walls with more than 50 mm (2”) of continuous insulation. New products have become available that may help solve some of the challenges. The design process, technology, and techniques for ensuring an air- and water-tight installation while mitigating thermal bridging will be presented, along with a range of thermal calculations and construction details to bring these solutions to life.

Presenter/Author

John Straube, PhD, PEng

RDH Building Science
University of Waterloo Faculty of Engineering

John Straube is a Principal at RDH Building Science and a cross-appointed faculty member in the School of Architecture and the Department of Civil and Environmental Engineering at the University of Waterloo. He conducts forensic investigations, assists with the design of new high-performance buildings and building products and leads research projects in the areas of low-energy building design, building enclosure performance, hygrothermal analysis, and field performance monitoring.

Non-Presenting Author

Daniel Haaland, MASc, PEng

Principal, Building Science Engineer
RDH Building Science

As a Senior Building Science Engineer, Daniel Haaland, MASc, PEng, supports RDH’s core practice areas, including new construction, research, and sustainability, while also sharing his knowledge with the industry as an author, speaker, and guest lecturer. As the leader of RDH's advanced analytics team, Haaland helps teams to assess and meet their ambitions for energy-efficient and high-performance building designs. Recognized as a leader in the field of finite element analysis for construction, he has authored multiple related industry guidelines and standards, such as CSA Z5010 and the THERM Passive House Window Simulation procedure.