Examining Methods for Preserving and Improving the Energy Performance of a Historic, Aluminum Framed Curtainwall System

2:00pm – 3:00pm

David Wach, PEng

Knowledge Level: Intermediate

Credits: This session has been approved for 1.0 IIBEC CEH. | This session has been approved for AIA 1.0 LU/HSW. | 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): Fenestration/Glazing, Sustainability/Resilience: SUS, Case Studies: CST

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

• Explain why historic curtainwall systems perform poorly compared to modern systems with respect to heat transfer.
• Discuss the life-cycle analysis of glazing components and associated embodied energy.
• Identify factors that impact a cost benefit analysis between retrofitting and replacing existing glazing systems.
• Recognize how specific boundary conditions around existing glazing impact the practicality of replacement.

Description
With respect to thermal performance, historic aluminum-framed curtainwall systems perform poorly compared to modern counterparts.. These systems are ideal candidates for replacement with newer thermally efficient systems during building retrofits. However, there are situations where replacement of the curtainwall system is not feasible due to other factors such as historic significance, constructability, or excessive costs. When a facade is designated as historically significant by local preservation authorities, the appearance of the curtainwall system must be maintained. This may be difficult with modern replacement systems, and customization may be cost prohibitive.  This session explores a method that was developed to thermally retrofit in-situ a historic curtainwall framing system while maintaining the original appearance of the system. The change in thermal performance is modeled to estimate improvements that can be achieved through retrofitting existing framing and compared to the improvement in replacing the existing framing. Finally, an energy cost-benefit analysis is conducted to account for embodied energy associated with the new framing system. The primary intended audience is designers and constructors focused on building restoration. Some background knowledge of building science fundamentals will assist the attendee's understanding.

Presenter/Author

David Wach, PEng

Senior Engineer , Engineering Link Inc.

David Wach currently works at Engineering Link’s Toronto office in the building envelope department as a senior engineer. At Engineering Link, Wach leads consulting teams on both restoration and new construction projects. He is formerly of Architectural & Metal Systems in Ireland, where his work focused on glazing and cladding system development and product sustainability

Non-Presenting Authors

Arthur Li, PEng

Project Engineer, Engineering Link Inc.

Arthur Li is a project engineer at Engineering Link, with more than seven years of experience in building envelope design and restoration in new and existing buildings. He has a master’s degree in civil engineering from the University of Toronto and a bachelor’s degree of applied science in civil engineering from the University of Waterloo. Li brings his expertise in thermal modeling into the evaluation of existing and new building envelope assemblies.

Paul Pasqualini, MASc, PEng 

Partner/Director, Engineering Link Inc.

Paul Pasqualini brings over 25 years of expertise in building envelope engineering. His diverse portfolio spans all industry sectors, including new building design and the restoration and repair of existing facilities and heritage sites. He adopts a holistic design approach, leveraging his technical expertise in building materials and construction technology to address and resolve complex environmental and maintenance issues effectively.