Recently, we sat down with Senior Engineer Justin Friend to talk about two special projects he’s worked on recently, The District at the Beltline and the Courtyard House.

Thanks for sitting down with us, Justin. Let’s talk about The District at the Beltline project first.

Justin: It’s my pleasure. The District at the Beltline is the revitalization of the existing three-building complex (previously the IBM Complex) located at 227 11 Avenue SW in Calgary. The concept aims to revitalize the complex into a campus-style environment with community, retail, and office workers in one central hub. The three office buildings are connected by a central “market shed” in the existing courtyard area.

Our role on this project was to review the capacity of the existing structure and plaza slab as well as provide the structural engineering services for the new market shed and alterations to the existing base building structure.

What were the unique challenges of this project? And how were they solved?

Justin: We encountered a couple of challenges on this project. The first was that the existing market shed is located in the existing courtyard area, directly above the below-grade parking garage. We had to review the existing structure to understand its capacity and determine if the existing structure could accept the weight of the new market shed, including the occupancy load from a future market.

With projects like this, upgrading of existing structural elements, especially foundations, can be costly. It was our goal to select a lightweight structural system to minimize the impact on the base building. In the end we selected a structural steel frame. The placement of the new columns were located adjacent to the columns below. We were actually able to place the columns such that the weight of the new market shed applied a counter-balancing load on the columns below, which removed some demand on the existing slab.

The second challenge was related to addition of a food court to the complex. The new food court is located on the main floor within the existing building. Two significant openings in the main floor slab were required for new mechanical and electrical service shafts. The location of the openings were detrimental to the performance of the existing slab system. Not to mention, the location of the opening was in an existing mechanical space, meaning pipes, equipment, and conduits are located everywhere, making construction in the space difficult.

The strategy was to have all parties attend the site to discuss which pieces of equipment could be decommissioned easily, and which pieces of equipment needed to remain. Our design responded to the many site constraints within the existing space. The final solution was that the structure was modified and supplemented with new foundations and steel columns. The locations of the new columns were selected based on ensuring the work presented the least impact on the existing mechanical system while also considering how the contractor would access the space to conduct the work.

It sounds like this was a great example of collaboration and seeking to design for the entire asset. Our holistic approach really came in handy. Any final thoughts?

Justin: The District at the Beltline is great example of revitalizing an existing building to bring it new life and vibrancy. The existing building is rather uninviting and intimidating to walk past. However, the new market shed and courtyard area will be a hub of activity when complete.

Now let’s discuss the Courtyard House. Earlier this year, this residence won the 2020 Prairie Wood Design Award in the Residential Category and has recently been featured in Avenue Magazine.

Justin: This was a really interesting, beautiful project. It’s a single-family residence located in Calgary that was designed by the Marc Boutin Architectural Collaborative.

Can you tell us about its unique features?

Justin: Architecturally, the house features exposed concrete walls and floors. To achieve this while still achieving appropriate thermal comfort, the foundations walls were constructed as 600mm wide concrete with an internal layer of insulation. The exterior wythe of concrete is non-structural, while the internal whyte of concrete is used to support the framing above. This type of exposed concrete construction is atypical in residential construction, so special attention was paid to the quality of concrete placement, type of formwork used, the process for stripping of the forms, and the quality and source of the concrete.

The house also features a cantilevered folded steel plate feature stair. Entuitive detailed the steel stair and concrete wall to ensure it met the design requirements while paying attention to the location of the welds to ensure they were visually concealed.

The second floor is conventionally framed from wood framing, but is supported on a primary steel beam and column system. Aesthetically, the architect chose a cruciform profile for the structural steel columns, which is an element that needed to be custom-detailed by our team.

Similar to the interior staircase, the exterior courtyard also features a cantilevered stair. Precast concrete was selected for the exterior stair treads to ensure the stairs had appropriate durability to stand up to Calgary winters. The precast treads were post-installed into the existing concrete retaining wall, which was not initially detailed to receive the stairs. Special attention was paid to the anchorage of the treads to the concrete wall. Heavy reinforcing bars were selected to carry the shear force, and the bolts were tensioned to an appropriate level to ensure there was no slack in the connection.

Finally, the exterior façade on the second floor features wood apertures that allow natural light into the house, while maintaining privacy from neighbors.

Wow, there are so many unique aspects to this house. But we hear there’s an even more special feature that was near and dear to the clients.

Justin: That’s for sure. The house is framed around the central staircase, which features a tortoise enclosure. Glazing for the tortoise enclosure doubles as a railing for both the staircase and second-storey guardrail. Structural steel framing was used to support the enclosure glazing.

This is truly a unique house in every way. Thanks for taking the time to share some insights into these projects with us, Justin.

If you’d like to learn more about the District at the Beltline or the Courtyard House, reach out to Justin Fried.

Courtyard House images courtesy of Bruce Edwards.