Reaching New Heights

A new residential project located in the heart of the Mayfair District has the potential to mark a new milestone for mass-timber technology. The Tresah project consists of two components:

Tresah East, a six-storey, wood-frame building offering 66 homes featuring ground-level townhomes; Tresah West, a 12-storey mass-timber residential high-rise offering 179 residences, including work/live spaces. It will feature exposed wood ceilings and beams, and the two buildings will share an underground parkade.

“Both buildings are of different scales yet have a shared architectural expression, characterized by richly coloured, brick-clad bases and luminous warm white facades,” says developer Mike Geric Construction.

Work on Tresah East began in November 2020 and is expected to be completed in March 2022, while work on Tresah West will commence in October 2021, with an anticipated finish date of December 2022.

Experience counts RJC Engineers is the official structural engineering firm on the project, complimenting their existing mass timber project portfolio. “Mass timber is a fast growing segment of the construction industry,” says Leon Plett, managing principal, RJC Engineers. He adds that in anticipation of an imminent revision to the 2020 National Building Code, B.C. has allowed early adopters in certain jurisdictions to use encapsulated mass-timber construction for up to 12 storeys. As such, Tresah will be one of only a few 12-storey, mass-timber construction projects currently in the works or in the approved pipeline in Victoria.

“In terms of engineering, I liken the difference between mass timber and concrete as the difference between playing with Lego and Play-doh,” says Plett. “Concrete is like Play-doh, in that it can be molded or flow into any form. Mass timber is moe like Lego in that you use the same form over and over again for maximum cost effectiveness, while still enabling creativity.”

The Tresah development will be noteworthy for several reasons, not the least of which is the mass-timber construction technology itself.

The two primary mass-timber technologies to be used in the project are cross-laminated timber (CLT) and glue-laminated timber (glulam, GLT). The former is fabricated from laminating lumber in perpendicular layers, resulting in strong panels that are ideal for building floors, walls, and roofs. Glulam is made by bonding individual pieces of lumber together with durable, moisture-resistant structural adhesives to form columns, beams, and headers.

One of the more interesting features of Tresah is the use of exposed wood versus encapsulated wood within the suites themselves to heighten the living experience for the homeowners. RJC Engineers has sought out the services of GHL Consultants Ltd. for help with the approval process.

Although Tresah will be the first high-rise, mass-timber construction project for Farmer Construction Ltd., it definitely won’t be the last. “It’s a relatively new form of construction. But we’re putting in the time now to become experts in the methodology of mass timber construction,” says Gerrit Vink, president, Farmer Construction. “We decided it was time to take the leap and invest in mass timber. We need to be a fully diversified company so that we can continue to satisfy the increasing needs of our clients.”

One of the key benefits of mass-timber construction (in addition to sequestering carbon) is the lightness of the construction itself. Plett estimates that the use of this type of construction in this particular project means that the building will be 30 per cent lighter. As such, the caissons can be smaller – which becomes very significant for this development, in particular, because of the site’s soil conditions.

“One of the challenges on this project is the marine clay soil,” says Monty Fitz, general manager, Don Mann Excavating. The company is responsible for excavating the entire underground parking lot – an area approximately 58,000 square feet or 1.5 acres in size. “Marine clay is very hard to work with; it’s very sticky, and it is very soft and unstable.”

As a result, Don Mann Excavating will import blasted and crushed rock to use as platforms for the excavating work. The company started on the site in November 2020 and hopes to be finished by late March 2021. “We have cleared the site and built the access roads for the shoring crew,” says Fitz, who estimates that his company will remove approximately 4,000 boxes of fill from the site.

Concrete reinforcing company, Tycon Steel Inc., has been charged with the supply and install of the rebar for the underground parking lot. The company expects to start on the project in February 2020 and anticipates that the work will take between seven to eight months to complete. “We’ve estimated about 700 tons of rebar for this project,” says Dan Seel, president, Tycon Steel Inc. “And we anticipate the need for between five to seven crew members.”

The fact that the project will include the mass-timber construction high-rise will not affect Seel’s work on the site. “I would describe it as a fairly typical project,” he says. “It’s a relatively flat space with a short lift so I don’t anticipate any challenges.”

With work on Tresah already underway, the City of Victoria is set to become home to a leading example of mass-timber construction. It’s a new standard for the region’s construction industry, one that will set the bar for more projects to follow.