Green building

Architecture in Harmony with Nature and the Environment

Visiting TOHU's Pavilion means entering a universe genuinely and thoroughly concerned by the environment. The Pavilion is green not only in spirit but in body too.

TOHU's building has been awarded LEED GOLD (Leadership in Energy and Environmental Design). This program imposes the strictest environmental standards, not only during construction but also in the management of the completed building. Thanks to the principles and practices that we put into effect, the Pavilion was one of the first projects in Canada to achieve such a high level of ecological performance.

Several technologies and other environmental elements are implemented into the building.

Passive geothermal power

TOHU’s building uses passive geothermal power to regulate the indoor temperature of its Pavilion: air from outside is pushed 2 meters underground through a pipe, then brought back inside the building. TOHU's geothermal wells are 60 meters long, allowing for the air to be pre-heated or pre-chilled by around 7 degrees Celsius, depending on the season.

Ice Bunker

The ice bunker is an alternative to conventional air-conditioning systems and is used to keep the theatre cool. This technology is on display in the reception hall through a glazed section of the floor. During a show, a mixture of water and glycol travels through tubes in the bunker, slowly turning the water into ice.

The process being spread over several hours, this technology requires very little energy overall. Moreover, rather than traditional CFC, TOHU’s cooling machines use HCF type refrigerating gas, which does not contribute to the depletion of the ozone layer.

Conventional geothermal Power

In 2007, five 325 feet geothermic wells were dug on TOHU’s premises. At this depth the temperature remains stable between 9 and 21 Celsius and allows for shallow geothermal energy. The principle is very simple indeed. The temperature being different underground and outside, the geothermic pump absorbs the heat underground and pumps it back into the building for heating purposes in winter. In summer, the hot air from the building is sent underground where it cools down before being blown back into the building. TOHU uses the wells to regulate the temperature inside its administration building all year round.

Biogas heating

An agreement with Gazmont is a perfect example of the way sustainable development technology was put into effect at the Pavilion. Located right next door to TOHU, Gazmont converts biogas from an excavation site at the Saint-Michel Environmental Complex (SMEC) into electricity.

The controlled combustion of biogas produces steam that then activates a turbine to create electricity. A portion of the hot water produced in the machinery's cooling process is pumped into the TOHU Pavilion and circulates through a network of ducts within the floor of the building (radiant floors). This technology does not emit any greenhouse effect gases and results in 20 to 35% savings compared to a conventional heating system.

Natural/hybrid ventilation

This system uses the 23-meter high performance hall’s funnel effect to evacuate the hot air. It uses 70% less energy than traditional ventilation systems. The air injected at low velocity to the hall warms up gradually, goes up and exits through the evacuation chimney located on the roof. When the outside temperature allows it, TOHU beneficiates from a natural low velocity and energy efficient ventilation system for its performance hall.

Recycled architecture

The ramps on the main stairway were made with recycled material from an old La Ronde bumper-car ride. Recycled metal beams from the Angus factories are also used for the Pavilion structure. The wood used for the entrance and terrace comes from cleaned and decontaminated CN railway ties. Finally, the exterior cladding of TOHU’s building is made of fibrocement, a mix of cement and wood. Such elements symbolize Montréal’s industrial heritage.

Green roofs

Since 2006, three plant surfaces cover the roofs of the ground floor office building, of the public toilets and of the North access point. The system is made up of a drainage panel, a root-resistant membrane and a mixture of soil, fertilisers and other organic substances. The selected plants require minimal maintenance. As well as absorbing and managing rainwater, this type of roof reduces temperature fluctuation, and cooling and heating load.

They help reduce heat islands in urban areas and also protect the roof membrane from UV rays, thus increasing its serviceable life.

Naturalized basin

The naturalized basin along the administrative building collects rainwater from the roof using a geotextile membrane and a layer of clay that retains the water.

This water is then dissipated by evaporation or percolation into the soil. The basin holds rainwater and avoids clogging the storm sewer system of the City of Montréal, while feeding the aquatic plants of the marsh.

Vegetable garden

The TOHU vegetable garden, in addition to providing a large amount of quality organic vegetables, is a fundamental part of urban agriculture awareness. As well as supplying the bistro in summer, the vegetables from the garden can be picked by visitors.

Discover this garden’s secrets on your next visit by asking for the "Thousand gardens at TOHU" self-guided tour book at the reception desk.


In collaboration with Miel Montréal, TOHU has joined the 45 Montréal institutions that have their own hive. This project will enable pollination by bees (which are now in danger in many parts of the world) on the Saint-Michel Environmental Complex.

The two hives contain between 80 000 and 140 000 bees. Why not get some of our honey from the bistro during your next visit to TOHU?

Get TOHU’s bees busy buzzin’! A $5 contribution can help support the environmental projects. Visit to get a bee busy buzzin’ and to subscribe to our newsletter.