Canadian Consulting Engineer

B.C. Cancer Research Centre

Located on West Broadway adjacent to the Vancouver General Hospital near the city's downtown, the new 21,460-m2 B.C. Cancer Research Centre is one of the largest cancer research facilities in Canada....

August 1, 2005   Canadian Consulting Engineer

Located on West Broadway adjacent to the Vancouver General Hospital near the city’s downtown, the new 21,460-m2 B.C. Cancer Research Centre is one of the largest cancer research facilities in Canada. It has a striking appearance, with two walls punched with round windows representing petri dishes, and a spiral stair enclosed in glass that reaches up the 15-storey height of the building.

With Stantec Consulting as the project manager, the $95-million project was completed ahead of schedule in December 2004 and $7 million below the approved budget. Keen Engineering was responsible for the mechanical engineering and played an important role in the sustainable design aspects. These have recently earned it a LEED Gold certification with the Canada Green Building Council. The building is expected to save 42% in energy costs and 43% on potable water demands compared to a standard laboratory building.

There are three major components: a laboratory wing, an office wing and a vivarium (animal holding centre). The laboratories need to be designed as flexible spaces to accommodate future changes, and so they were designed with an interstitial service space between each floor to hold the electrical and mechanical systems. The ample space allows the systems to be serviced and reconfigured during renovations without causing disruption.

The office wing is more dense, with the floor to ceiling height restricted to 2.9 metres, resulting in two office floors for every interstitial laboratory level. There was no ceiling space for a conventional air system in the offices, so instead, an in-slab radiant piping system provides heating and cooling — a relatively new application in North America. Warm or cool water circulates through the piping, and the concrete mass absorbs and retains the energy. In addition to room sensors, temperature sensors are provided at various heights in the floor slab to help predict the flywheel effect of the thermal mass. Computer simulations were done to predict the effect on the occupants’ comfort, and the studies were used in refining the design of the building envelope and glazing. Ventilation air is supplied through vents in the offices and corridors. The windows are openable and protected by sunshades.

As a laboratory and research centre, the building uses large amounts of outside air to meet the ventilation and exhaust requirements. To reduce the energy use, the designers recovered all the building exhaust heat to warm up the outside air intake. As a result no supplemental heating energy is required until the outside air temperature is below -3C.

Since several areas in the building require year-round cooling from the chilled water system, the chiller has to be operated all the time. By using a heat recovery chiller, the engineers were able to use its rejected heat to temper the outside air in the spring, fall and winter months. Instead of pumping the warm condenser water from the chiller to the cooling tower, it is routed to a heat exchanger and used to heat the building as the heating system was designed for 45C. This approach has proved to be very effective and efficient.

In the high glass-enclosed spiral staircase that sits on the outside of the building on the west side, air does not need to be mechanically cooled because motorized openable windows at the top and bottom of the stairwell remove the buildup of heat. The entire HVAC system for both the laboratory and office wings is controlled and orchestrated through one central direct digital control building automation system. (see below)

Above the laboratories wing an important feature is the use of bifurcated strobic plume fans on the roof which ensure that air is exhausted 30 feet above the rooftop and dissipated to a safe distance. These fans eliminated the need for high stacks and created a pleasing building profile.

In the laboratories variable volume fume hoods are used to reduce the volume of outside air being brought in. They are controlled either by the time of day or by the laboratory staff adjusting the height of the sash.

In the vivarium, the humidity, temperature and ventilation conditions are tightly controlled. The Bio-safety Level 3 laboratories also require stringent room pressure controls. They have to be kept at negative pressure and the controls have to be able to rapidly isolate the area in case of contamination. The space also has HEPA filters in the exhaust system to prevent bacteria or viruses escaping.–BP

Owner: B.C. Cancer Foundation

Mechanical consultant: Keen Engineering (Blair McCarry, P.Eng., Robert Abbenhuis)

Project management: Stantec Consulting (Michael Kennedy)

Structural consultant: Glotman Simpson

Electrical consultant: RADA

Architect: Henriquez Partners/IBI Group

Controls: E.S.C.

General contractor: Ledcor

BUILDING CONTROLS

Orchestrating the systems

By Steve Egglestone, E.S.C.

Our first concern in the B.C. Cancer Research Centre project was building a network of DDC panels that could communicate effectively, considering the network would consist of 498 panels. When you have a DDC panel layout this large, the key is keeping communication traffic under control. Our plan was to use a high speed Ethernet backbone for all the primary control panels on each floor, and have all variable air volume controls networked on the slower RS485 to the primary control panels. We also installed redundant Ethernet cabling with smart switches so that if there were a disconnection, the smart switch will automatically change over to the alternate cable without any effect on the building operation.

We thought that building integration could be a challenge due to the proprietary protocols used by each vendor. However this case was quite the opposite. Chiller integration through the Ethernet BACnet protocol connection worked on the first attempt. We were able to see all the normal control points we would provide, plus an array of internal information from the chiller that could normally only be seen from the chiller control panel

Predicting what level of slab heat and cooling to provide was a definite challenge. We came up with a method using calculations based on outdoor air temperature and estimated building thermodynamics. This allowed us to anticipate what the slab set points were to be 72 hours in advance.

Coming up with the right graphical scheme so the building staff could understand what was happening in a particular laboratory was critical since there may be three or four VAV boxes and three or four fume hoods per area. Typical graphics show the single piece of mechanical equipment and its control points only. The key was to provide comprehensive graphics so that the user could see all the components of an area and how they interact with each other.

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