Ontario Power Generation 

Oshawa Headquarters

 
 
 

Ontario Power Generation set out to unite its various corporate offices into a single, modern facility that embodies collaboration, efficiency, and long-term sustainability. Repurposing the former GM headquarters brought new life to an iconic site. The project was recognized with a 2026 Award of Distinction from the Association of Consulting Engineering Companies - Ontario Chapter.

OPG selected Oshawa as its new corporate headquarters, purchasing and redeveloping a well-known building - the former General Motors (GM) administration building — a 285,000 ft2 facility with five levels (four storeys plus a lower concourse).

The project brought together OPG’s non-station staff from across the Greater Toronto area and Durham Region under one roof, transforming the existing structure through extensive interior and exterior renovations. Upgrades encompassed all major building systems, focusing on enhancing performance, comfort, and environmental responsibility.

HH Angus and Associates played a pivotal role as mechanical and electrical engineers, IMIT and lighting consultants, owner’s engineer, plumbing/fire protection/life safety designer, and commissioning authority.

The overarching goal was to create a future-ready workplace capable of supporting OPG’s operational and cultural needs for the next 40 years — targeting a net-zero carbon footprint and integrating leading sustainable design strategies throughout.

Meeting the objectives
HH Angus’ design solution had high sustainability and energy aspirations and involved the adaptive re-use and re-development of the GM administration building in Oshawa. HH Angus’ Commercial and Angus Connect teams came together for this project.

The project team successfully navigated a series of challenges that tested both creativity and collaboration, ultimately demonstrating their ability to deliver excellence under demanding conditions.

Materials and equipment
The unique use of materials was in fact the ‘re-use of materials’, significantly reducing deconstruction waste and embodied carbon. Much of the existing HVAC equipment was optimized (e.g., terminal heating and cooling devices) to enhance performance and capacity, rather than replacing the distribution network.

Internal resources, experience and expertise
To meet the demands of the accelerated schedule, the project team of mobilized a robust internal team, drawing on resources from across the firm. This collaborative effort, made possible by the firm’s size and depth of expertise, allowed us to maintain quality and precision while delivering on time.

Apart from strategic reuse of existing infrastructure, to accommodate increased occupancy, the design team included the use of energy recovery and thermal storage to allow system capacities to be sized below the peak demands to get the most out of the cost and embodied carbon of the equipment provided.

Outcome
Through ingenuity, collaboration, and technical excellence, the team successfully overcame these challenges—delivering a high-performance, cost-effective design that met the client’s objectives and ambitious goals, and reinforced their trust in the team’s ability to deliver innovative solutions under pressure.

 

SERVICES
Mechanical Engineering | Electrical Engineering | IMIT Design | Lighting Design | Owner's Engineer | Plumbing Design | Fire Protection | Life Safety  Design | Commissioning Authority


PROJECT FEATURES
Size: 285,000 ft2, 5 levels (four storeys plus lower concourse) | Completed 2025 | Recipient of a 2026 ACEC/OEPA Award of Distinction for engineering excellence


LOCATION 
Oshawa, Ontario


KEY SCOPE ELEMENTS
Interior and exterior base building renovation | Condensed design schedule | Mandatory sustainability requirements | Repurposing of original HVAC equipment | Heat pump technology | Air-to-air energy recovery | All new DALI Lighting Control System


 
 
 
 

 

 

Collaborative process 

An interesting challenge was meeting the fixed project budget while delivering design integrity. To address this, the team dedicated many hours to an intensely collaborative process—partnering closely with manufacturers, vendors, and contractors to identify cost-effective solutions that preserved the client’s vision and design intent. Through innovative thinking, open communication, and strategic value engineering, the project was successfully delivered within budget while maintaining both functionality and aesthetic integrity.

 
 

Repurposing building systems

A further challenge emerged with the new interior layout, pushing existing building systems beyond their designed capacity. Rather than opting for a costly and disruptive full replacement of the distribution ductwork, the design team developed a strategic, resourceful solution. By introducing terminal heating and cooling devices to supplement the existing infrastructure, the required system performance was achieved efficiently and sustainably.

 
 

Hamilton Health Sciences Centre (HHSC)

Greenhouse Gas Reduction and Resilience Action Plan

 
 
 

HHSC asked HH Angus to develop a strategic and comprehensive GHG Reduction and Resilience Action Plan to guide HHSC in meeting provincial and federal greenhouse gas reduction targets for 2030 and, eventually, "Net Zero" by 2050.

The scope of the work HH Angus provided covered the following HHSC sites (totaling approximately 3,200,000 ft2):

  1. McMaster Children’s Hospital
  2. Juravinski Hospital and Cancer Centre
  3. Hamilton General Hospital
  4. West Lincoln Memorial Hospital
  5. St. Peter’s Hospital
  6. Ron Joyce Children Health Centre
  7. David Braley Research Building

HH Angus developed a Strategic GHG Reduction and Resilience Action Plan (GRRAP) for HHSC to support their goal of achieving carbon neutrality by 2050. This plan included establishing a GHG inventory for Scopes 1 and 2, in addition to forecasting future emissions. (Scope 1 emissions include direct emissions from on-site combustion, and have consistently represented the majority of total emissions. Scope 2 emissions are associated with purchased electricity, steam and/or chilled water.)

GHG reduction targets were set in alignment with leading international frameworks such as the SDGs (sustainable development goals), SBTi (science-based targets initiative), and UNGC (UN Global Compact).

Some key considerations in developing the GRRAP included:

  • Aging infrastructure and deferred maintenance
  • Emissions from natural gas combustion
  • Carbon tax financial risk
  • Integration of redevelopment with decarbonization
  • Uncertainty in future district energy and waste heat
  • Embedding Equity, Diversity and Inclusion and sustainability culture

HH Angus completed an analysis of existing energy and sustainability plans, policies, and facility assessments to identify key opportunities for GHG reduction, while adhering to GHG Protocol standards. The newly created GRRAP document outlined the necessary steps, measures, infrastructure requirements, and financial scenarios needed to meet or exceed the proposed GHG reduction targets.

The implementation plan focused on energy conservation, electrification, renewable energy generation, and zero-carbon building solutions. Additionally, HH Angus provided HHSC with a GHG Manager tool to facilitate ongoing scenario modeling.

SERVICES
Prime Consultant | Mechanical Engineering | Electrical Engineering


PROJECT FEATURES
7 sites totalling 3,200,000 ft2 | Completed 2025


LOCATION 
Hamilton, Ontario


KEY SCOPE ELEMENTS
Mechanical consulting, including ASHRAE Level II energy audit; evaluation for energy conservation measure, review and evaluate maintenance records, capital redevelopment plan | Electrical consulting, including utility analysis, site capacity evaluation | Feasibility study


Royal Inland Hospital

New Patient Care Tower

Royal Inland Hospital is a tertiary level acute care hospital serving a catchment area of approximately 220,000 residents in the city of Kamloops and throughout the Thompson, Cariboo and Shuswap regions of British Columbia.  

The 290,625 ft2 new Phil & Jennie Gaglardi Patient Care Tower (PCT) is a nine-storey building that includes a surgical floor, 13 operating suites, patient floors for mental health and medical/surgical beds, a neurosciences and trauma unit, perinatal centre, labour and delivery rooms, and neonatal intensive care unit. There are also two underground parking levels, administrative and clinical spaces on three lower floors, an intermediate mechanical floor, and 3 inpatient levels topped by a penthouse containing the heating, cooling, and emergency power plant.

Phase 2 consists of a number of renovations within the existing facility, including a completely renovated Emergency Department. Phase 1, which opened in July 2022, has achieved LEED Gold certification. HH Angus provided mechanical and electrical design services for the PCT, which was constructed adjacent to the existing hospital under a P3 contract.

Designed with direct input from local healthcare workers, the PCT streamlines access to hospital services through a single main entrance. A new post-anaesthetic recovery room in the adjacent existing facility’s renovated space will be constructed in Phase 2. Other clinical spaces include a substance use inpatient unit, a child and adolescent mental health crisis intervention program, maternal and child services, and respiratory therapy services. Non-clinical spaces include reception, patient registration, a rooftop helipad, underground parkade, retail space and a new home for the Royal Inland Hospital Foundation.

Modern reception interior with wood ceiling and circular lighting


The mechanical design included energy-efficient heating and cooling systems with a variety of heat recovery features. The project had an ambitious energy use target and HVAC systems were designed with this benchmark in mind. Current estimates predict 24% savings in energy costs.

HH Angus was able to solve a problem the Hospital was having with the existing distributed hot water boilers by upsizing the new plant to serve the majority of the hospital campus. The ventilation design includes redundant capability and outbreak control, and exhaust air heat recovery, as well as providing for future flexibility.

The Health Authority expressed an interest in the ability to conduct smudging ceremonies in any patient room without having to make significant modifications to the current ventilation design and infrastructure included in the project.  HH Angus found a means for using the ventilation system as originally designed and applying a unique operational sequence to minimize capital cost changes while providing the ability to undertake smudging activities in any of the patient rooms on the Medical/Surgical and Mental Health Adaptive inpatient units.

A central focus of the design team was to work with the commissioning team to ensure proper operation of the new facility. The design team is now helping monitor ongoing operations to recover and reuse as much waste heat as possible. This effort concentrates on the heat recovery chiller plant operation to meet as much of the building’s heating load as possible using waste heat. This contributes to minimizing the production of GHGs from heating energy sources and, in turn, improves decarbonization for the new facility. New electrical services include a 25 KV service from BC Hydro serving a new outdoor substation powering the existing campus and PCT. New redundant 25kV to 600V FR3 transformers feeding the new tower were provided in the new main electrical room. Three new 2MVA diesel generators provide emergency power backup to the new patient care tower and the rest of the existing campus if utility power is lost. 600V distribution on both utility and generator power are provided with high resistance grounding to increase resiliency and reliability in the event of a single ground fault. Numerous low voltage systems were provided including fire alarm, lighting control system complete with daylight harvesting, circadian rhythm tunable lighting in the Neo-natal ICU, and electrical metering.

SERVICES
Mechanical Engineering | Electrical Engineering


PROJECT FEATURES
Size: 290,625 ft2 | Status: Phase 1 completed 2022


LOCATION 
Kamloops, British Columbia


KEY SCOPE ELEMENTS
Ongoing technical infrastructure upgrades | Installed heat exchangers to link the cooling plant to the Deep Lake cooling system | LEED Gold certified


Helipad Design

The rooftop helipad is served by a number of mechanical and electrical systems to help keep the pad surface clear of snow and ice and to provide appropriate safety lighting to meet all requirements. Fire protection and life safety systems, such as foam suppression, were carefully coordinated and designed to ensure full coverage and containment in the event of a discharge.

Systems Integration

 Integration with the existing hospital systems was a significant challenge and required numerous connections to the adjacent facility. Requiring multiple site visits, it was determined the two facilities could be successfully integrated by enclosing an outdoor courtyard between them, transforming it into a four-season space that will benefit patients, staff and visitors. On the electrical side, backfeeding the existing facility with new 600V HRG generator backup required careful analysis of existing distribution to ensure compatibility for all existing equipment to the new 3 wire distribution on emergency power. A detailed sequence of operations for black start sequence and retransfer of automatic transfer switches to normal was developed and commissioned to ensure proper operation for different failure scenarios.

TD Bank

Living Roof

“The Green Council [tenant representatives] has made it clear, through a commitment to action, that sustainability is a core value of TD Centre tenants.”


David Hoffman, then-General Manager. TD Centre

At the TD Centre’s iconic towers in downtown Toronto, TD Bank’s Living Roof offers both environmental benefits and some much-needed green relief from the usual hardscape views had by occupants of the Centre’s towers. It covers 22,000 ft2 and is planted with creek sedge grasses, a hardy semi-evergreen native species tough enough to survive the extremes of Toronto’s climate. Annual energy savings from the green roof are approximately $23,000. This is achieved by reducing summer cooling and winter heat loss by 25%. 

HH Angus provided mechanical and electrical engineering for the green roof installation and irrigation system, as well as the project’s preliminary Feasibility Study. To avoid over-watering, the irrigation system features a sensor that shuts down the irrigation system when it rains. This sensor also reduces irrigation when the water received during previous rainfalls or irrigation has not yet evaporated.

In order to evaluate the requirements for mechanical and electrical design for the irrigation system, the ceiling plenum for the single story building below had to be surveyed. The storm water drainage system was original and would need modification and updating. The existing plumbing was modified to allow connection of the new irrigation.

Installation of dedicated electrical circuits and automated controls was required in order to operate the self-draining irrigation system. The controls were ceiling mounted with remote computer access. Rain spray heads, valves, head sensors, pattern nozzles, valve boxes, and stainless roof drains were incorporated.

Before the design could be executed, rainwater calculations were carried out based on Environment Canada data, along with spreadsheets detailing storm water run-off. These calculations assisted in sizing the storm water piping and locating roof drains and spray nozzles.

A roof leak detection system was also designed, along with a new soil pipe vent stack through the Pavilion roof, and a gooseneck conduit for rooftop wiring. A new replacement filter rack was added to the roof air vents.

SERVICES
Feasibility Study Plumbing Design | Mechanical Engineering | Electrical Engineering


PROJECT FEATURES
Size: 22,000 ft2 | Status: Completed 2015 | Annual energy savings through reduction in summer cooling requirements and in winter heat loss


LOCATION 
Toronto, Ontario


KEY SCOPE ELEMENTS
Feasibility study | Rainwater calculations | Plumbing design with supporting mechanical and electrical design and engineering | Roof leak detection system


 

Sustainable 

design 

TD Bank's Living Roof represents tenant values and is a bold expression of collaboration in support of environmental stewardship

Honouring the design

The green roof’s grid pattern mimics Mies van der Rohe’s original design for the pavilion roof. This was done to respect the ‘designated heritage site’ aspect of the TD Centre.

Images courtesy of Flynn Canada

St. Michael’s Hospital

Barlo MS Centre

Canada has the highest rate of multiple sclerosis in the world; in fact, the disease is known internationally as ‘Canada’s Disease’. St. Michael's Hospital in Toronto is one of North America's busiest MS centres. It has been caring for people with MS since 1981, and now treats 7,000 patients.

The new Barlo MS Centre offers one-stop care, bringing together neurologists, nurses, social workers, neuropsychologists, physiotherapists, occupational therapists and speech therapists in a world-leading treatment and research centre for multiple sclerosis. The 25,000 ft2 clinic has been constructed on the top two floors of the new Peter Gilgan Patient Care Tower.

HH Angus’ mechanical scope for the fitout of the shelled space included ventilation, plumbing, medical gas, heating & fire protection, and controls. Our electrical scope covered power, lighting, communications and security.

Unique aspects of the project's design included:  presentation to the client of a number of ventilation strategies to address the shortage of air supply available to the design, and a reworked ventilation strategy under a very aggressive schedule to redistribute and extend air to the clinic from an existing air handling unit that was previously feeding another floor.

Some of the project challenges included:

  1. The addition of a compounding pharmacy late in the design, for which additional requirements had to be vetted to meet NAPRA. The team took advantage of early works to investigate available shaft space for running new biological exhaust to the roof.
  2. Design activities had to be scheduled concurrently with testing and commissioning still underway at the time for the main Patient Care Tower.
  3. Ceiling construction and new structural constraints limited accessibility. The team used 3D imaging and Revit to coordinate all ceiling elements requiring accessibility, in order to integrate services into areas with wooden slatted ceilings.
  4. The team took advantage of early works to coordinate structural openings for future ventilation in order to limit ceiling interference for the fitout design.

SERVICES
Mechanical Engineering | Electrical Engineering | Lighting | Plumbing | Communications Systems | Security Systems


PROJECT FEATURES
Size: 25,000 ft2 | Status: Completion 2021 


LOCATION
Toronto, Ontario 


KEY SCOPE ELEMENTS 
Two floor clinic fitout | Variety of room types and functions | Custom smoke venting and fire alarm zoning to accommodate feature staircase


Patient area at Barlo MS Centre

Achieving the design vision

We worked closely with the architect to modify the existing fire alarm zoning and smoke venting strategy in order to accommodate a new mezzanine on Level 17. This allowed the architect to achieve the design vision for the feature staircase without the use of smoke baffles.

 

Variety of functions

The space includes a variety of room types, including exam rooms, gym, medical infusion centre, group physiotherapy studio, auditorium, cognitive lab and a pharmacy.

Lab area at Barlo MS Centre

Click here for the St. Michael’s Hospital video feature on the Barlo MS Clinic.