Architectural Drawing Set

Conclusion

As the construction of tall mass timber buildings increase and these structures continue to grow in height, it is necessary to use efficient balcony solutions that are optimized for this building method. Providing robust solutions to the balcony structure and durability in mass timber or tall wood buildings will help position timber as a viable structural alternative to the conventional concrete or steel construction. The balcony mock-up investigated the application of timber as a main structural material with a combination of selective steel members, focusing on the main research objectives. While it is not a comprehensive comparison or examination, the balcony mock-up studied what it means to have a face-mounted timber balcony system to a primary structure consisting of a glulam beam and a column through a unitized CLT wall panel.

Prefabricated from a combination of structural steel members, exposed timber glulam strut, and cross-laminated timber (CLT)/dowel-laminated timber (DLT) decking coupled with a wood decking finish, the balcony system deployed in the site mock-up comes as a modular unit, easing the on-site installation with minimal disruption to the building envelope while reducing the thermal bridging with minimal connection points.

The balcony mock-up research demonstrated the feasibility of delivering a viable thermally broken balcony solution in a mass timber building, in addition to advantages of employing a prefabrication construction approach that streamlines construction scheduling and sequencing and coordination among various consultants and trades. As we prepare this report, further post-construction monitoring and evaluation of how the timber elements react to various outdoor weather conditions over time are being carried out to holistically assess the durability of this balcony design and construction solution. A report from the post-construction evaluation will be provided once the monitoring process is complete, to provide further update on the following research questions: 1. Understanding the penetration of water through balcony edge details to recognize how the final structure will handle water.

2. Monitoring the performance of different types of decks complete with a durable/translucent finish as needed. 3. Logging moisture characteristics of the balcony timber components via installed moisture monitoring sensors.

Additional investigation is required for fire protection. Although it is not installed in this mock-up, sprinklers are required for all EMTC building balconies, even if they are noncombustible, when they are over 610mm in depth based on current BC Building Code and Vancouver Building Bylaw 2019. This is based on a concern with vertical fire spread in EMTC buildings at the exterior. Recent fire demonstrations involving exposed CLT compartments has provided data that supports the potential for a code change to relax balcony sprinkler criteria in EMTC buildings.

Image Sources

Page 14: Figure 16 & 17: Step over requirements and Minimum height to guard railing Source: City of Vancouver, Bulletin 2016-002-BU, Balcony and Patio Doors in Houses and Dwelling Units, July 7, 2016

Appendix