quickly attracted corporate clients to relocate their head
offices. TNS consists of several hundred thousand square
feet of office, retail and residential space, and a plaza for
public gatherings, outdoor concerts and movies.
Although the Portage Avenue Scotiabank Tower
was sold in 2017, when Scotiabank moved its corporate
offices to TNS in 2018, the bank planned to maintain the
branch location and update it to meet their needs. Like
many downtown property managers/owners, Scotiabank
decided a renovation, which included updated accessibility
features, was crucial to maintaining and attracting
new tenants. This included the demolition and renovation
of the existing Scotiabank offices, updates to the
vault and upgrades to the mechanical and electrical systems.
The renovations began in September 2018.
The issue of access
According to the City of Winnipeg’s Public Works
department, Portage and Main is the city’s third-busiest
intersection, with an average of 81,000 vehicles passing
through the intersection on an average weekday. With
its location on one of Winnipeg’s busiest intersections,
access was the first major hurdle to overcome.
Many factors were considered when creating the construction
plan and schedule, including the lack of space
for material offloading and staging, building occupancy
during construction, the age of the structure and the
tower’s proximity to road and foot traffic. To solve the
offloading and staging concern, PCL worked with the
City of Winnipeg’s permit department to close nearby
Main Street between 9 a.m. and 3 p.m., to provide as little
disruption to rush hour traffic as possible. Arrangements
were also made for the pickup of refuse bins, which were
placed on the street each evening and removed by 6 a.m.
the following morning.
Demolition
Driven by the need for tenant improvements, a new
elevator and stairwell would be constructed between the
tower’s main floor and concourse level. A challenge for
construction, but a win for tenants. To add the elevator,
PCL first needed to remove the concrete slabs on the
main and concourse levels.
While removing interior sections to make room for
the staircase, the aging building required the installation
of temporary shoring to support the concourse
slab, the support beams underneath and the concrete
walls. To achieve the necessary stability, the shoring was
installed on temporary mud sills inside the building’s
crawlspace. Along the exterior walls, PCL also installed
diagonal hollow structural section bracing 15 feet apart,
along with a W18 beam running the length of the wall.
Diagonal bracing was then installed on a ¾-inch-thick
plate with eight ½-inch rods at each pile location. An
opening was made on the exterior of the building to
allow for the movement of the structural steel bracing
and piling equipment directly from the street to the
building’s crawlspace.
Concrete cutting and placing were conducted by PCL
as a cost-savings measure.
An unexpected challenge
Once the building was stabilized, the PCL project team
worked to remove the concourse slab. Original drawings
provided by the client showed a concrete tower crane
pad leftover from the building’s construction under the
concourse slab, which would need to be removed to make
room for the new elevator foundations. However, PCL
crews discovered the actual tower crane pad was nearly
twice the size indicated by the drawings and over five
feet thick. It was also so heavy that none of the equipment
on site could remove it.
Consideration was given for reducing dust, noise and
vibration to ensure the building’s current tenants were
not negatively impacted by demolition activities. PCL
investigated and chose Ecobust, a controlled expansive
demolition agent composed of a biodegradable powder.
The powder is mixed with water and poured into predrilled
cavities, where it then expands with a force of
more than 20,000 pounds per square inch.
Ecobust provides controlled breaking to cut or demolish
concrete and rock without any noise, vibration or
dust, making it ideal for situations like the Scotiabank
Tenant Improvement project in which the building was
occupied during demolition. It is designed to break reinforced
concrete and rock into manageable pieces. It is
often used for concrete demolition, rock crushing and
cracking, quarry work and mining when conventional
methods are not suitable, such as restricted access locations
and busy or occupied buildings. The product could
be used by PCL’s own forces, which made the solution
efficient and cost-effective.
Using Ecobust, the crane pad was demolished and
removed in stages over the next four months.
Tenant considerations
Close coordination with the owner and tenants helped
minimize additional impacts of construction such as air
quality. PCL installed additional ventilation equipment
to circulate the air. Exhaust scrubbers were required
on all equipment to control the risk of air pollutants
during demolition.
In accordance with the project specifications, much
of the demolition work early in the project was done
in the evenings to minimize the disruption and impact
on daytime bank operations. As the project progressed,
the work shifted to daytime hours. By working with the
City of Winnipeg, Scotiabank and the trade contractors,
PCL minimized the disruption to tenants while achieving
a successful completion of the upgrades to 200
Portage Avenue.
Due to its location in such a high traffic zone, the piling
work for the Scotiabank Tenant Improvement project
was done overnight over multiple weekends to minimize
the impact to both street and pedestrian traffic.
CONTINUED ON PAGE 36
PROJECT SPOTLIGHT
34 Issue 4 2021 www.pilingcanada.ca
/www.pilingcanada.ca
