however, the unique challenges created by the tight quarters
of the site in busy downtown Toronto required both to
be constructed simultaneously. Furthermore, the owners of
the Massey Tower project donated a strip of land to Massey
Hall as a necessity in order to enable both the Massey Hall
Revitalization and the new Massey Tower construction to
take place. Neither project would have been possible without
the other.
Neighboring the property to the north is the former Bank
of Toronto building (built circa 1905) and to the south is
Heintzman Hall, which was occupied by the famous piano
company, “Heintzman & Company,” from 1912 to 1971.
Additionally, to the southeast of the property is the Elgin &
Winter Garden Theatre (EWG) which was built in 1913 and
is a landmark of its own in the Toronto theatre community.
The close proximity of existing foundations and walls of
these heritage buildings (each over 100 years old) – and the
need to protect them – were a complicating factor for the
foundation and shoring work of both projects. The new structures
required foundations to be installed deeper than and
very close to the footings of the adjacent heritage buildings.
Due to the sensitivity of these old footings, the shoring and
caisson drilling had to be completed from several different
benched elevations using different equipment and techniques
to suit the needs of each phase of the foundation work.
The project’s shoring and caisson foundation works were
undertaken and executed under a carefully planned construction
sequence by Deep Foundations Contractors Inc.
(deep). deep overcame unique challenges and provided solid
foundation solutions for both projects to rise as successors in
the Massey Hall legacy.
The foundation works
To effectively excavate for both projects, a single shoring
system connecting the two properties had to be designed.
deep’s work for the projects included a secant wall shoring
system, braced with soil and rock anchors, for four levels of
underground facilities for Massey Tower and two levels for
Massey Hall. The excavation for Massey Tower was founded
in sound bedrock. The Massey Hall excavation, on the other
hand, did not extend as deep, so caissons and structural piles
were required to support the new structure’s loads. Massey
Hall’s foundation design consisted of a combination of 28
structural shoring piles and 29 caissons, which were used to
help carry the loads for the new structure to bedrock.
Maximizing real estate meant shoring walls were exceptionally
close to the existing buildings. Eighty per cent of the
piles on the project had to be drilled with the mast of the drill
rig within inches of historic buildings. Crew and operators
had to be constantly vigilant to ensure that equipment did
not make contact with any of the structures or that the drilling
and vibrations did not cause cave-ins or compromise any
of the existing foundations.
Each of the buildings immediately surrounding the project
had to have their footings exposed and located. Once the
footing locations were verified, the shoring design and drilling
methods were determined to match the field conditions.
In many cases, the edge of the drilled hole had to be inches
PROJECT SPOTLIGHT
Rendering of Massey Hall Revitalization
50 Q2 2017 www.pilingcanada.ca
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