January 1, 2010
by Canadian Architect
PROJECT Manitoba Hydro Place, Winnipeg, Manitoba
INTEGRATED DESIGN TEAM Kuwabara Payne McKenna Blumberg Architects, Smith Carter Architects & Engineers, Transsolar KlimaEngineering, Prairie Architects Inc.
TEXT Peter Sampson
PHOTOS Gerry Kopelow and Eduard Hueber
With the Copenhagen Summit having come to a dismally weak resolution on global emissions targets, and with Canada’s even more appallingly vague and fidgety position on the issue of climate change, many Manitobans are in a celebratory mood for their recent performance in this regard. Amidst this weakness on ecological futures, the province is home to ex-premier-turned-ambassador Gary Doer, known internationally for his strong track record on the environment. He was flown to Copenhagen to rescue the federal government’s dwindling hopes of escaping the talks unscathed. More significantly, the energy-rich province is also home to the Best Tall Building in America in 2009 awarded by the Council on Tall Buildings and Urban Habitat (CTBUH), based in Chicago.
Located in downtown Winnipeg, the 22-storey headquarters for Manitoba Hydro was designed by Kuwabara Payne McKenna Blumberg Architects in conjunction with Smith Carter Architects and Engineers of Winnipeg, and climate engineers Transsolar of Germany. Opened earlier this year with its LEED Platinum target firmly in sight, Manitoba Hydro Place is proving to be one of the most efficient passive-energy office towers in North America.
Let’s face it, nothing says regional head office like Winnipeg’s skyline and so it is with some measured sense of pride that Winnipeg’s newest addition to the stumpy vista beat out contenders from cities across the continent for the Award. What is remarkable is that this 696,000-square-foot winner is outperforming its own energy reduction targets, no small feat in Canada’s coldest city where even modest efficiency milestones are challenging in the smallest of residential infills. With an annual Canadian temperature swing of 70 degrees Celsius, Winnipeg’s -35 degree winters make most Canadians wince at the thought of 100 percent fresh-air intake. “If we can build like this here,” says Tom Gouldsborough, District Manager of Corporate Services and the visionary project manager for Manitoba Hydro, “then we can build like this anywhere.”
Despite Canada’s poor reputation in Copenhagen, on its home continent, Manitoba Hydro Place–known locally as the Hydro Tower–is clearly a new kind of symbol for progress in this century. Manitoba has been making a name for itself on issues of sustainability through an extensive and complex commitment to ecological construction and performance. Much of this effort is spearheaded by the country’s fourth-largest utility, a provincially owned corporation that boasts some of the lowest rates on the continent, yet still promotes energy conservation as a fundamental mandate. In these low-dollar-per-square-foot times, it is hard not to observe, despite the $278-million price tag, how far the public dollar has been stretched here. A city of 700,000 people in a province of 1 million is home to the continent’s leader in the evolution of office towers. And what’s more, in the face of recent international criticism of Canada, of the 25 consulting experts commissioned for Manitoba Hydro Place, all but one firm was Canadian.
The general well-being of architecture in this country stands to benefit from Manitoba Hydro’s commitment to building not the largest nor the tallest tower in the country, and not the slenderest nor the most formally outstanding. Instead, a quiet and didactic working laboratory for passive and sustainable energy performance is set in an urban environment and is open to the public. Bruce Kuwabara, the project’s design architect, tells me that “this just might be one of the best ways to spend public money that I can think of.” Manitoba Hydro Place is challenging the nature of conventional large building targets in Canada. “It is long overdue,” Kuwabara says, “that we raise our standards.”
On track to achieve LEED Platinum, the project marks what Kuwabara describes as “a critical moment for Canadian architecture. The era of the hermetically sealed box is over. And so is the way we deliver projects of this stature and complexity.” Manitoba Hydro Place is a game-changer. “The Class A office tower is a thing of the past,” he says. “The whole notion of B’s and A’s is a ridiculous leftover of modern efficiency. Isn’t it weird that in the 21st century, we’re actually talking about how good the quality of air is–that this is something we should actually talk about? How did we get here?”
Collected data for Class A office towers in Canada indicates that most cold-climate office towers operate in a range of 400-550 kWh/m2 per year. Gouldsborough confirms that the average Manitoba office space utilizes 495 kWh/m2 per year. When the design of Manitoba Hydro Place began five years ago, the average Canadian office space used 550 kWh/m2 per year. Today, Winnipeg office towers are in the 325 kWh/m2 per annum range because of Manitoba Hydro initiatives over the past decade. He also notes that new performance guidelines for Class A office towers in Canada are targeting energy consumption at 260kWh/m2 per annum.
Current consumption patterns at Manitoba Hydro Place demonstrate a projected energy use of 88 kWh/m2 per annum, 66 percent better than the Model National Energy Code for Buildings (MNECB). “And that surpasses the project target of being just 60 percent better than the MNECB,” Gouldsborough says.
The high-performance envelope is comprised of a double-glass curtain-wall system containing operable windows and automated solar shading. The system is comprised of low-iron glass which maximizes natural daylight entering floorplates, reducing demand for artificial lighting. Shallow floorplates capitalize on this daylighting strategy: the workspace is only 11 metres from envelope to core, and while this is two metres deeper than code standards established in Germany around daylight design, it is shallower than local contemporary examples. Where lighting does occur, advanced T-5 fluorescent fixtures are used.
Extending below the single storey of underground parking is the province’s largest geothermal system with 280 boreholes, each one 125 metres deep. These tap the earth’s natural energy storage for both heating and cooling purposes. Because of the raised floor ventilation provided at each floor, the bulk of heating and cooling radiates from exposed concrete slabs above.
Three south-facing, six-storey “winter gardens” are lungs that condition incoming air. By capitalizing on available solar energy, these suspended atria add to a bevy of social spaces that perform vital functions in the passive operations of the complex. Here, multi-storey waterfalls flow down steel wires humidifying or dehumidifying air, depending on the season. Below, green roofs atop the three-storey podium feature sweet grass, a sacred plant of local Aboriginal cultures, and other native prairie plants. These assist in the reduction of stormwater runoff and are said to convert carbon dioxide to oxygen, minimizing the building’s urban heat-island effect. Most importantly, an advanced fully integrated building management system coordinates ventilation, heating, lighting and solar shades throughout the day ensuring that the structure operates as a single entity while actively responding to changes in climate, use, environment, and operational requirements.
At the north apex of the atrium, a 115-metre-tall solar chimney rises expressively over Portage Avenue above the bulk of the complex to capture the sun. It provides an energy-free passive ventilation source by employing the natural stack effect of a high-rise structure and drawing spent interior air up and outwards.
The CTBUH provides an annual internationally juried awards program to assess advances in tall-bu
ilding technology on a continent-by-continent basis. This year’s jury statement noted that Manitoba Hydro Place “was designed to be completely site-specific. The design could not be transplanted to another city and still work, thus making it the perfect response to the seeming homogenization of the world’s skylines.” This is quite an ironic description for a building that clearly gives a nod to Gordon Bunshaft’s canonical 1952 Lever House in New York City, a building many consider to have singlehandedly ushered in the generic International Style to the skylines of America. Bunshaft is credited with the statement “concrete, steel and glass are the natural materials of North America,” a broad notion of site specificity, to be sure.
Bunshaft’s seminal headquarters transformed the urban skyline in the 20th century because it revolutionized envelope constructability and performance through the design of the curtain wall. Manitoba Hydro Place pays homage to the Lever House both formally and in the reinvention of the curtain wall into a triple-glazed performative skin that mediates the behaviours of interior and exterior environments in a way Bunshaft could not have imagined. It subverts the generic nature of the overdone glass box and podium by contextualizing it in a local, living, ecological response to place.
One major factor of place is the urban context. Hydro’s mandate went beyond technological performance. The renewal of resources included social resources. The commitment to downtown development was not second nature to Hydro; word on the street is that it came at the insistence of Glen Murray, Winnipeg’s mayor from 1998 to 2004. Gouldsborough comments that when he helped broker the deal to merge Winnipeg’s hydroelectric utility company with the Province’s Crown utility corporation, the proviso was that a new head office be built downtown. Hydro’s 1,800 employees were seen as an obvious and much-needed stimulus to the downtown economy.
Stefano Grande, the Executive Director of Winnipeg’s Downtown Biz, comments that “a few decades from now, when we look back on what some of the turning points for downtown were, the decision to relocate 2,000 workers in the heart of our city will be right up there.” He anticipates the precedent will spark a decade of revitalization. A host of cultural institutional landmarks currently under construction indicate that renewal in the city’s core is well underway.
Manitoba Hydro Place amalgamates 15 of the corporation’s two- and three-storey suburban leaseholds. Prior to the new facility, 95 percent of the employees drove to work. Hesitancy among employees to move to the downtown location was countered with a careful Change Management assessment conducted by Hydro to complement a host of corporate incentives ranging from participation in Winnipeg Transit’s EcoPass program. Six months after moving, Hydro cites that 50 percent of the relocated employees are leaving their cars at home. As a result, Manitoba Hydro has been able to reduce its parking demand in the downtown sector and has observed a five-fold increase in employee use of public transit compared to the previous year. Gouldsborough adds, “energy reductions were important, but primarily we did this to create a healthy infrastructure for our employees.”
Further positive impact to the downtown extends to the type of leasing opportunities offered in the base building. These are intentionally limited in an effort to stimulate the support of local businesses and to encourage staff to experience their city. Though space exists for a child-care facility, research determined that the nearby YMCA’s child care program was under-enrolled and would benefit from the arrival of a new demographic.
The project was commissioned through an Integrated Design Process in which each team member was interviewed, selected and contracted directly by Hydro. Dudley Thompson, Principal of Prairie Architects, was retained as the Advocate Architect for the project. Kuwabara credits him with enabling a team of high-calibre experts to come together. As the first member of the team, Thompson spearheaded the Integrated Design Process and worked closely with Hydro to establish LEED objectives. In the pre-design and research phase of the project, Thompson arranged a field trip for Hydro executives to tour 10 high-performance buildings across the US and Europe.
When it came to the selection of the Design Architect for the project, a number of international architects known for their success with bioclimatic design were interviewed along with KPMB. These included British architect Norman Foster, Stuttgart-based Behnisch Architekten, Germany’s Christoph Ingenhoven, and US-based Gensler. “With that roster, I can’t say we came to Winnipeg expecting to win,” says Kuwabara. Thompson recalls that “Bruce’s presentation was simple and direct; we knew who we would be dealing with. The other groups came with too many people; we could not get a sense of who actually would be doing the work with our team, if any of them. There was something about Bruce’s ability to listen and his interest in people that convinced us that he would work with the team to create an appropriate urban building for both Hydro and Winnipeg.”
“The process depends entirely on respect,” says Kuwabara. It is only as good as the individuals who participate in it. If there is distrust or stubbornness at the table, he says, the process is entirely compromised. Kuwabara cites his own inexperience with IDP when he began the project. “I guess because I had not gone through it, I had no preconceptions of it–it was an open-minded event. I think many of us approached it this way. It worked well on this project because it was so well organized.”
Both Kuwabara and Thompson suggest that without Thomas Auer of Transsolar, whose expertise in passive bioclimatic architecture and energy modelling spans two decades, Manitoba Hydro Place could not have been what it is today. “Thomas brought with him a wealth of experience from Europe that doesn’t yet exist here,” says Kuwabara. His ability to react quickly to design ideas based on that experience was an immeasurable asset to the team. “Thomas was in my office one day looking at some of the schemes that we had on the go before a big presentation to Hydro,” says Kuwabara, “and he casually commented that if we rotated one of our schemes 90 degrees, we could capitalize on the prevailing southerly winds and sun of Winnipeg.” Despite being from Germany, Auer’s intimate research and modelling of weather patterns around the city made him the resident expert on local climate. “That was a beautiful moment in the process,” says Kuwabara, “everything just snapped into place. The urban design strategies that we were wrestling with to limit shadows on Portage, the effort to strengthen pedestrian connectivity on the site combined with the towers being situated so as to open the atrium to the south, all of a sudden everything was in place.”
At $400 per square foot, Manitoba Hydro Place exceeds financially the objectives of many of local developers building in a slow-growth city. “With the payback period for construction measured over 60 years instead of the more typical short-term investment “scenario,” says Kuwabara, he feels the commitment to such a long-range forecast reinforced the design team’s commitment to quality workspaces, systems durability, and the overall urban integrity of the project. Gouldsborough claims that many of the project’s major design elements–the bright open floor spaces, high ceilings, operable windows, advanced workstations, and the 100 percent fresh-air ventilation system–are designed to maximize employee productivity and comfort as well as minimize energy consumption. These have untallied financial advantages for any organization and are clear objectives as we move into the second decade of this century. CA
Peter Sampson is Principal of Peter Sampson Architecture Studio in Winnipeg and is an Adjunct Professor at the University of Manitoba’s Faculty of Architecture.
Client Manitoba Hydro
Integrated design team Kuwabara Payne McKenna Blumberg Architects (Design Architect); Smith Carter Architects & Engineers (Executive Architect); Transsolar KlimaEngineering (Energy/Climate Engineers); Prairie Architects Inc. (Advocate Architect/LEED Consultant)
Structural Halcrow Yolles, Crosier Kilgour & Partners Ltd.
Landscape Phillips Farevaag Smallenberg, Hilderman Thomas Frank Cram
Interiors KPMB Architects (Base Building and Public Space), IBI Group, Number Ten Architecture Group, ESP Environmental Space Planning (Interiors, Office/Workspace)
Construction Manager PCL Constructors Canada Inc.
Building Envelope Brook Van Dalen & Associates
Water Features Dan Euser Waterarchitecture
Geothermal Groundsolar Energy Technologies, Omnicron Consulting Group
Quantity Surveyor Hanscomb
Code & Life Safety Leber Rubes
Traffic/Access/Parking ND Lea Engineers & Planners
Lighting Pivotal Lighting Design
Microclimate RWDI Inc.
Vertical Transportation Soberman Engineering
Geotechnical Engineer/Hydrogeologist Uma Engineering
Municipal & Site Services Wardrop Engineering
Area 695,742 ft2
Budget $278 M (Project Cost)
Completion September 2009
Rising along Winnipeg’s Portage Avenue, Manitoba Hydro Place ushers in a new era of office building for a city that already has a rich history of high-rise architecture.
One of three south-facing atria that acts as a winter garden and lung for the building, tempering fresh-air intake through the use of passive solar heating.
PASSIVE MECHANICAL SYSTEMS KEY
1 Shoulder Seasons/Summer Mode
air is drawn naturally in through large operable windows
2 South Gusting Winds
abundant in Winnipeg, direct air into south winter gardens
3 Winter Garden
six-storey-tall atria act as the building’s lungs, drawing fresh air in and preconditioning it before it enters the workspace
4 Winter Mode
air is drawn in through outer mechanical units and heated by geothermal field
5 Inner Heating and Cooling Units
further condition air as it passes into the raised floor distribution plenum
24-metre-high water feature either humidifies or dehumidifies air as it enters the building
limited to 200 spots to encourage employees to take public transit, and use parking spaces in the city
8 Solar Chimney
115-metre-high solar chimney uses stack effect
9 Shoulder Seasons/Summer Mode
draws used air up and exhausts it out of the building
10 Exposed Ceiling Mass
uses radiant heating and cooling; warm air rises and is drawn into north atria via natural pressure differences
11 100% Fresh Air, 24/7
in all office spaces is drawn through the raised access floor
12 Winter Mode
chimney closes, fans draw warm exhaust air down, and recirculate it to warm the parkade. Heat exchangers recapture heat and return it to south winter gardens to preheat incoming air
13 Geothermal System
280 boreholes 125 metres deep draw excess heat or cold stored within the soil to condition the building
A variety of cladding material was used on the project, ranging from low-iron ultra-clear glass to tyndall stone and a tyndall stone-inspired frit applied to a unitized curtain wall.
In addition to improving the view for many office workers, the green roof helps reduce solar heat gain and mitigates storm water runoff.
A series of time-lapse photographs brilliantly conveys the special quality of light found only on the Prairies.
1 office lofts
2 hanging wood screens
3 access bridges
4 water features
5 geothermal well field
7 green roof
8 south grove
9 public plaza
A Oriented due south, the sixth-floor atria act as passive solar collectors in the winter, allowing the low winter sun to warm the air in the atria, and penetrate deep into the core of the building.
1 During the summer, horizontal blinds deploy and protect the atrium from the harsh summer heat and glare.
2 Six-storey-tall communication stair encourages physical activity and interdepartment communication.
3 Air is preheated at the exterior bench using glycol circulated through the geothermal field.
4 Humidification or dehumidification is provided by a water feature in each atrium.
5 A second set of fan coils at each floor level further heats and cools the air as it is drawn into the raised floor at each level.
B Overhead direct-indirect lighting uses integrated occupancy and daylight sensors to minimize energy consumption, and make maximum use of daylight.
6 Exposed radiant ceiling slab heats and cools the space efficiently.
7 Computer-controlled louvre blinds reduce glare and solar gain.
8 Computer-controlled exterior window vents allow air into the double skin when temperatures allow.
9 Large-span structural concrete ribs provide flexible column-free office lofts.
10 Manually controlled interior windows allow occupants to individually control airflow and temperature at their workstations.
11 The perimeter edge of the slab has been shaped to allow for maximum daylight penetration into the building.
12 Exterior glazing uses extremely clear low-iron-content glass to allow more light into the workspace lofts; Low-emissivity coatings help to reduce heat penetration at the faade; Where a double skin is not employed, faades utilize high-efficiency triple glazing.
A view along Portage Avenue illustrates the building’s classic Modernist origins.
The three-storey atrium that constitutes the main entrance also acts as the building’s hub and connection to an outdoor public plaza.
Various atria throughout the building provide space for socializing and impromptu meetings.
A view down the central atrium.
An open stair terminates the north-facing atrium and adds warmth with its Douglas fir cladding.
One of the many attractive stairs in the building, a gesture that encourages employees to use them instead of elevators whenever possible.
Typical tower floor layout concept
— east and west faces offer a double-skin faade with occupant-controlled natural ventilation
— floor-to-ceiling height of 3.31m (10’10”)
— floor-to-ceiling glazing, typical
— overhead radiant heating and cooling
— air and services distributed through raised access floors
1 contained spaces — 8’0″ demountable solid and glass partitions
2 enclosed spaces — 8’0″ demountable solid and glass partitions, with glass transoms to ceiling
3 atria — north/south multiple floor atriums, with communication stairs
4 core — elevators, services and storage
5 open work stations — 50″ tall panels
The south faade of the building, overlooking the new public plaza.
The 115-metre-high solar chimney uses the stack effect to help ventilate the tower.