Star-gazing building demonstrates environmentally-responsive architecture

Located within Montreal’s iconic Olympic Park complex, this project was the winning entry in a two-stage international competition. The project brief called for an intervention that would humanize the rather bleak site, which included an existing underground parking structure adjacent to the Olympic stadium. Together with the nearby Botanical Gardens, Insectarium and Biodome, the Planetarium is part of Montreal's 'Space for Life', the largest concentration of natural science museums in Canada.

By Marc Chenouda, M. Arch.

The planetarium is an educational, cultural and scientific museum for astronomy. The architectural response was guid-ed by a desire to connect the building to nature, the place from which the vastness and beauty of the night sky can be experienced most profoundly. Another goal was to make this experience accessible to all, not simply to patrons of the Planetarium itself.

With sustainability a central concern, the decision was made to retain the parking garage and utilize it for part of the building program. This strategy reduced both heat loss and unwanted solar heat gain while offering a wonderful opportu-nity to explore access to natural light by sculpting the space and creating mood and ambiance.

The concrete structure is draped with an undulating, acces-sible green roof that connects the various levels of the site and creates an attractive amenity where people can linger amid trees, shrubs and public art. Two large conical skylights project through the vegetated roof, symbolizing the connec-tion between nature and sky, and bringing natural light deep into the building.

These skylights, together with a portion of the upper floor, are new con-structions built on top of the existing structure. No additional foundations were necessary. The ground floor of the building houses the public spaces, including the main entrance, two star theatres, exhibition spaces and a cafe. The second floor houses the administrative offices, while the lower level serves as the link with the adjacent Biodome, and includes related activity areas, change rooms and a dining room.

The Milky Way Theatre, which seats approximately 200, is the traditional astronomical facility where visitors study and learn about the stars in the sky. In the dubbed Chaos Theatre, visitors sit back and relax on bean bags and are taken for a twenty minute multimedia odyssey through the universe. There is also a permanent interactive exhibition with projectors and multi-media games.

The green roof is the most visible ‘facade’ of the new building. Custom-made fescue turf creates a durable and drought-resistant ground cover that permits public access and requires minimal irrigation. Rainwater is har-vested in a closed loop system that collects water from areas of permeable paving, both on and beyond the site, redistributing it via a drip irrigation system controlled by the building’s own weather station.

The building contains two large 40,000 litre rainwater reservoirs that capture water from the roofs and terraces. Filtration and treatment systems ensure that the harvested water is suitable for use in the toilets and urinals.

The main energy strategy for the Planetarium was to recycle excessive heat or cooling from the adjacent Biodome, which runs on an open-loop geothermal system. This previously wasted energy supplies more than half the Planetarium’s energy needs. The complemen-tary demands of the two buildings optimizes the use of the geothermal open well system. Extreme weather demands are supplied by high efficiency gas boilers which also act as an emergency back-up system.

The hybrid ventilation and heat recovery systems, manufactured in Manitoba, meet the acoustic requirements of NC20, while recapturing 80-95% of the latent and sensible heat energy from exhaust air, both winter and summer. The fresh-air central system has a water atomization humidification adiabatic system which allows low temperature energy usage as a source of heat.

PROJECT CREDITS

ARCHITECT Cardin Ramirez Julien + Ædifica

LEED CONSULTANT EXP

CONSULTANTS Patenaude-Trempe Inc. Experts Consultants ACOUSTIC Dessau [Acoustique]

UNIVERSAL ACCESSIBILITY Société Logique

LANDSCAPE ARCHITECT Fauteux et associes architectes paysagiste

CODE CONSULTANT Sylvie Destroimaisons

TECHNOLOGIC INTEGRATION Go Multimedia

PHOTOS Stephane Brugger, Espace pour la vie [Diane Pinard], Vincent Audy, David Giral

PROJECT PERFORMANCE

- Energy intensity [building and process energy] = 702 MJ/m2/year
- Energy intensity reduction relative to reference building under ASHRAE 90.1 1999 = 47%
- Potable water consumption from municipal sources = 2,187 L/occupant/year
- Potable water consumption reduction relative to LEED reference building = 70.6%
- Reclaimed and recycled material by value = 20%
- Regional materials [800km radius] by value = 20%
- Approximately 85% of the existing parking structure was retained