Building Systems and Construction Features
Although not necessarily apparent to the visitor, the design team and the County of Grey invested a great deal of time and money in the design of features intended to save energy. Museum standards require this building to have a high degree of control over humidity and temperature. This requirement means that humid air will be introduced into the building during the winter and that the building could require a low level of air conditioning even during cooler weather. This means that the building envelope is a critical part of the energy efficiency and long-term viability of the construction materials.
The building envelope is highly insulated and features a sprayed-in-pace rubberized air and vapour barrier at the inboard side of the exterior wall with 8 inches of batt insulation (containing recycled slag material from steel production) and sprayed-in-place polyurethane foam at the outboard side. We also incorporated a unique double wall design that will allow future exhibit designers, electricians and others to route new wiring, hang new exhibits or otherwise penetrate the interior gypsum board without risk of damaging the critical rubber air/vapour barrier. This is essentially a second interior, non-load bearing, stud wall that follows the exterior wall and protects the expensive air/vapour barrier from damage.
The mechanical system utilizes ground source heat through a horizontal ground loop buried to the north of the building and heat pumps usually used for ice making in hockey rinks. Further, the Ontario Building Code required that an on site storage tank be available to supply water for the sprinkler system and on site fire fighting. The heat pump loops also use this water as part of the ground loop heat sink. The heat pumps themselves are Canadian technology and use denatured grain alcohol as the heat transfer medium rather than water or caustic substances such as ammonia. This system is connected to the rooftop equipment described below, a snow melting system in the entrance courtyard and a band of in-floor heating around the entire perimeter of the building. This will ensure that the area at the juncture of the foundation wall and the floor slab is warm and free of condensation that could generate mould in the relatively humid environment required for artefacts. The foyer is also heated in the floor for its entire extent in order to keep this surface dry.
Efficient rooftop heating, ventilation and air conditioning units augment the ground loop system. These have natural gas as a back-up heat source and contain humidity control. These units will handle heating and cooling during spring, early summer and fall with the ground loop system and gas will provide additional heat at the coldest part of the winter while electricity will provide the energy for cooling during the peak of summer.
Lighting fixtures (except for display lighting) use high output fluorescent lamps to conserve energy and occupancy sensors are intended to turn lights off in certain areas when no movement is sensed.
~ G.M. Diemert Architect Inc.
