Energy Efficiency Attributes of the Ian Ross Building

The Ian Ross Building

The Ian Ross Building is named after Professor Ian.G. Ross, former Dean of Science and Deputy Vice- Chancellor, who was a driving force behind the establishment of undergraduate and post graduate engineering at ANU. The building, which is occupied by the Faculty of Engineering and Information Technology (FEIT) was opened on 15 November 2000.

The Ian Ross Building was designed by Collard, Clarke and Jackson Architects who were recently awarded the Sustainable Architecture Award at the 2001 ACT Architecture Awards- for their design of the Ian Ross Building. The new award goes to "a brave and robust demonstration" that a building taking a simple and fundamental approach to the basics of ecologically sustainable architecture can still have a significant impact in other areas. The building generates "memorable architectural elements- dramatic towers, soaring internal celestory windows, defining interior circulation....unusually placed windows, exposed masonry- and importantly the ability of occupants to control the environment of their spaces"

General Environmental Systems

The Ian Ross Building uses passive environmental systems as a means of providing occupant thermal comfort and energy efficiency. It responds to concerns for low maintenance, low life cycle cost and ecologically sensitive design with emphasis on passive ventilation. In summary, systems have been developed and incorporated to provide the following:

• solar shading controls space radiant temperatures during summer while allowing sun penetration during winter for passive heating;
• natural ventilation systems remove internal heat loads, provide air movement and provide oxygen to occupants;
• ceiling mounted fans provide air movement when windows are closed on hot days and distribute heat to lower occupied levels on cold days;
• internal blinds provide glare control;
• insulation, double glazing and large areas of internal building mass help provide passive cooling through control of radiant heat loads;
• hydronic slab heating that utilizes the mass of the building providing radiant heating and efficient cost effective operation;
• solar hot water panels reduce energy demands on water heating;
• high efficiency light fittings reduce energy demands and room heat loads;
• air conditioning provides a back-up to high heat load areas on level 2 which cannot always maintain thermal comfort by passive means alone.

Heating System

A hydronic heating system that is suitable for future integration with solar hot water collection has been installed to heat the building during winter. It currently uses a gas fired boiler to heat the water. Slab heating is a storage heating system that utilises the mass of the floor to dispense heat to the space. Consisting of PVC pipes embedded in the concrete slab the system provides 40-45% reduction in energy consumption over the traditional wall mounted radiators. A high percentage of radiant heat transfer from the floor allows occupants to experience even teperatures throughout the space. The system has been zoned to take into consideration usage patterns, internal loads and conduction loads on each space.

Building Fabric

The building fabric of the Ian Ross Building provides high levels of both insulation and thermal mass to passively assist the control of radiant heat loads from both the occupants and machinery such as computers. External walls are either double brick or reverse brick veneer insulated to a minimum of R2.5. The majority of the external walls are double brick with the level 1 ceiling slab having an exposed rib for extra surface area for cooling.Level 1 floor slab has perimeter insulation and all windows are glazed. The roof has two layers of insulation, R1.5 insulation directly under the roof sheeting and R3.5 at the ceiling plane. The external walls and roof both have reflective foil sarking.

Daylighting and Solar Protection

A C-Shaped building footprint orientated towards the nothern sun reduces the depth of the building and allows a large amount of natural light into the internal spaces.Where the building is at its deepest, within the central wedge shape, the internal spaces are supplemented by a celestory on level 2 that runs the entire length of the circulation street. Level 1 spaces are given acess to diffuse lighting via the ventilation chimneys that also act as light wells bringing light from the celestory above.

Roof overhangs, sun shades and varying window shapes depending on orientation help to keep to solar heat out during summer and maximise solar penetration for heat gain during winter. Daylighted to shaded areas is maintained through the use of translucent polycarbonate shades. Large deciduous existing trees have been utilized as an extra layer of sun control in summer negating the need for shading the south east facade. Internal reflective blinds provide localised glare control within each space.

Artificial Lighting

Low energy light fittings featuring electronic ballasts, silver lux reflectors and T5 luminaires provide energy savings and reduce heat load in rooms. Zoning of the lights provides additional energy savings as areas can be switched off when suitable daylighting exists.

Natural Ventilation

Two natural ventilation networks exist within the Ian Ross Building. A fully automated system and a manually operated system. An automated system is provided to all the 'public zones' within the building. These zones include the class rooms, design studios, staff rooms, seminar rooms, circulation and gathering spaces. The ventilation is controlled like an airconditioning system and uses a temperature controlled BMS. All the windows and dampers are controlled by the BMS which takes into account internal temperature, ambient temperature, wind velocity, wind direction and rain. A night purge function has been incorporated into the system and will operate during the high temperature summer periods to purge the stored heat from the building overnight. All motorised windows have a manual override to open and close windows as desired. Ceiling fans are used to provide air movement during hot periods when windows are closed.