Ecologically Sustainable Design — Planning And Construction Standards
File: EMP Policy and Procedures. Version Number 1: Date: 8 January 2003
The Facilities and Services Division is responsible for all major construction and refurbishment projects established by the University. The Division is also responsible for the management of minor works and the backlog maintenance program.
The University is committed to established good standards of environmental management in all relevant activities and with that in mind, the Division has developed ESD standards that are to be applied to all planning and construction work undertaken by its staff or contractors.
Commercial buildings, through their construction and operation, account for the majority of Australian greenhouse emissions and waste production as well as having many other significant environmental impacts. Buildings that follow the principles of environmentally sustainable design (ESD) seek to minimise these impacts throughout the lifecycle of a building.
The overiding aim of the Australian National University is to establish buildings that produce no waste, either in the construction of the building and associated equipment and, after occupancy, in the operation of the facility. Whilst this is an ambitious plan, the following standards are a first step in ultimately achieving that aim.
Energy - Building Fabric
Design & Comfort Issues
The University wishes to achieve buildings that minimize the ongoing use of mechanical services through passive design principles. Operating energy use has the most significant impact over the lifecycle of an average building so investment in an efficient building fabric is well worthwhile.
Thermal Comfort in ANU Buildings
The maximum summer design temperature for a naturally ventilated building shall be 30 degrees C with a maximum of 5% (30 hours) of summer working hours (8am till 6pm) above 26 degrees C.
Specific design principles to reduce building energy use are detailed below:
- Where tight temperature and humidity control is not critical (e.g. offices, circulation spaces) space conditioning will be achieved through natural ventilation. Air-conditioning will only be provided in areas where temperature control is critical for operation (e.g. laboratories, libraries), or passive design techniques will not meet an acceptable level for human comfort (see above). Mixed-mode systems that provide natural ventilation for the majority of time and airconditioning only in extreme temperatures are acceptable.
- Where natural ventilation is proposed for summer cooling of a building, a thermal model of the proposed building design shall be undertaken to verify performance.
- The best available building orientation will be utilised to reduce solar gain in summer and maximize solar gain in winter (generally the longest faces of the building facing north/south).
- Integration of thermal mass in the internal building fabric is encouraged to provide temperature moderation in all temperature extremes.
- Where operable windows are included as part of a passive ventilation system they shall be easy to operate and include flyscreens. They will also present no obvious security risk. At minimum operable windows in public areas shall be automatically controlled.
- The minimum thermal rating for complete roof systems on enclosed internal areas will be R4.0. This is a system rating that includes bulk insulation, foil, airspaces and roof structure.
- The minimum thermal rating for complete wall systems shall be R2.5.
- On-ground slab floor construction to have a minimum R2.0 rigid insulation installed on the slab edge. Elevated floors shall have a minimum thermal rating of R2.0.
Windows (Glazing & Frames)
To ensure a thermally sound building envelope the following window specifications will apply:
- Overall building glazing is to be kept to a minimum and to not exceed 40% of total wall area.
- Windows are not to extend below 600mm height where anticipated standard usage is likely to obstruct low windows with furniture. Likewise glazing above 2000mm should only be installed if it can provide glare-free daylighting and displace electric lighting.
- Access to daylighting will be maximised without introducing excessive glare or unwanted heat gain.
- Window assemblies to include appropriate weather stripping to prevent air leakage.
- A detailed assessment of the cost benefit of advanced glazing systems (double glazing, low-e & tinted) will be provided by the designer.
- Windows to provide suitable external shading based on orientation as outlined below:
| Orientation || Shading |
Effective horizontal shading to minimise summer sun entry.
Vertical shading to reduce early morning summer sun entry
Vertical shading to reduce afternoon summer sun entry
The above window performance standards aim to minimise heat gain in summer and heat loss in winter. Most of this performance standard can be met with solar passive design. Where site restrictions preclude optimum design more advanced window systems such as additional external shading or high performance glass may be required.
- All external doors to be adequately protected with storm seals and draught excluders.
- Entries should be provided with some form of cover and wind protection.
Reducing the wattage of installed lighting whilst still meeting required lighting standards is a central part of lighting energy efficiency. To provide a guide for the selection of lights and their layout the following maximum lighting intensity guidelines are proposed:
| Type of Area || Target (W/m2) |
General Offices, Computer rooms, Lecture Theatres & Classrooms
Restaurants & Retail
|Foyers, Corridors, Stairs & Toilets || |
The lighting intensities stipulated above have been adapted from the Property Council 2001 energy efficiency guidelines.
The control of installed lighting so that it operates only when required is also an important part of lighting energy efficiency. The following control strategies for lighting are proposed:
- All intermittently used rooms such as meeting rooms, tea rooms and utility rooms will be fitted with either timer switches or motion sensors (whichever is deemed most appropriate and cost-effective).
- Controls will be fitted to the building lighting system to allow out of hours lighting control via a local system or through connection to the University BMS. Such controls should flexible so they can align with changing occupant usage of the building.
- Suitable switching will be provided so that local control of lighting can be achieved (A maximum of 500W of installed lighting per switch).
Heating, Ventilation and Airconditioning
To provide an overall picture of building energy efficiency all new buildings will be required to meet energy intensity targets. Energy intensity targets are expressed as the amount of energy used in a year per square meter of floor space in a building. The building design team are required to calculate and submit energy intensity indicators with Final Sketch Plans for approval.
Many building energy intensity indicators are a single figure that include complete building energy use – HVAC, lighting, hot water, lifts & equipment or ‘plug’ load (appliances). For the ANU the major energy users in buildings are HVAC, lighting and ‘plug’ load. As the ‘plug’ load in buildings can vary based on specific building usage it has been excluded from this target. Hot water and lifts are also ommitted as they can vary greatly based on building types and usage. This leaves HVAC and lighting which still on average represent the majority of ANU building energy use.
The energy intensity targets for HVAC & lighting are as follows:
|Area of consumption ||Energy intensity target |
100 MJ/m2/pa (electric**) or 175 MJ/m2/pa (gas**)
160 MJ/m2/pa (electric**) or 280 MJ/m2/pa (gas**)
90 MJ/m2/pa (average 10w/m2 @ 2500 hrs/yr)
108 MJ/m2/pa (average 12w/m2 @ 2500 hrs/yr)
*Laboratories or other areas with critical temperture and humidity requirements and/or lighting levels requirements.
**Differing targets for elctricity and gas are provided due to the different energy intensity of these energy types.
The above figures are based on a building operating 2500 hours in a year with all spaces heated and cooled. Figures can be adjusted for different occupancy rates.
The higher target for laboratories and other specialist areas reflects more stringent HVAC requirements and potentially higher illumination levels required for laboratory tasks.
The following specific criteria are also stipulated to ensure that systems are both designed and operated to achieve maximum energy efficiency.
- An economy cooling cycle with up to 100% outside air and the potential for heat recovery shall be assessed for all HVAC systems and detailed cost-benefit calculations provided to the project coordinator with final sketch plans.
- All HVAC systems (including split systems) will be connected to the ANU BMS or have an independent 365 day programmable timer and/or manual reset timer.
- Effective zonation and control shall be provided to deal with different usage within a building.
- All motors above 1 kW and with a duty cycle of more than 1500 hours/yr will be high efficiency models.
- All motors with a variable load and > 10kW with >3000 hour duty cycle shall include a variable speed controller.
- To enable the ongoing measurement of HVAC and lighting energy consumption sufficient metering shall be provided in all new buildings (and major refurbishments where feasible) to provide separate consumption data for HVAC, lighting and plug load where annual energy use for each is anticipated to be > $10,000/yr.
To reduce energy use from hot water systems the following standards apply:
- Minimise length and size of supply pipes (also insulate accordingly – see below).
- Selection of the most efficient system for the user requirements based on the following classification:
Hot Water Usage Profile
High constant load
Solar or high efficiency gas storage
High variable load
Small electric storage (<150 litres) with supplementary insulation (R1.5 under base and around sides) or locally installed instantaneous electric
Pipe Work and Duct Work
To reduce friction losses in piping from bends (and thus reduce pumping energy costs) due consideration must be taken when designing pipe layouts. This is a design activity that does not cost any extra and can deliver ongoing savings.
Hot water supply piping can be extensive inside and external to University buildings so should be fitted with a minimum 25mm insulation to reduce heat losses.
Operation & Maintenance (O&M) Manuals
Operating instructions for all mechanical systems shall include start/stop procedures and energy efficient operating procedures. With the potential for a high turnover of users in the university environment it is essential that information on the efficient operation of plant and equipment is readily available to staff.
Reduction in water consumption can return significant financial and environmental benefits to the University. In order to realize these benefits the following requirements are stipulated:
- All hand basins and showers will be fitted with water efficient (AAA rated) fixtures or a flow restriction system that achieves a flow rate of no greater than 9 liters per minute.
- All landscaping will use drought tolerant plants and efficient irrigation systems to reduce irrigation water consumption.
- The option for local capture and use (e.g. rainwater tanks) and/or absorption of storm water (e.g. through landscaped swales) will be assessed by the design team for each new facility.
- The option for reuse of grey water in the building will be assessed by the design team.
- Impervious landscape surfaces that encourage stormwater surface runoff will be minimized.
- Prevention of loss of soil during construction through effective surface water and wind erosion control. This will also assist in reducing sedimentation to storm water drains and dust pollution.
- Stormwater drains are to be located so that the storage or handling of waste and chemicals could not result in the pollution of the stormwater system. This will require effective bunding of waste and chemical storage facilities and the provision of a drain to sewer.
Materials & Waste
The ANU population of approximately 15,000 staff and students creates the waste equivalent to that of a small town. Much of this waste can be avoided or recycled, providing both financial and environmental benefits. The selection of materials for use in construction or as a consumable can also have significant lifecycle environmental impacts in regard to energy and water use as well as waste production. The following standards aim to reduce waste production and the environmental impacts from materials used in building construction.
- Sufficient permanent covered space shall be provided to install waste and recycling facilities to service co-mingled, cardboard, paper and general waste collection within the building precincts. Size of these facilities to be in accordance with the ‘Development Control Code for Best Practice in Waste Management in the ACT’. Further, the internal design of the building should include appropriate space for the installation of recycling bins that service the needs of building occupants, keeping in mind that convenience generally promotes higher recycling rates.
- During construction or refurbishment work separate bins shall be provided to recover timber, glass, metal, concrete and other recyclable materials from the waste stream.
- The use of recycled or remanufactured materials over virgin products is encouraged where this does not attract a significant lifecycle cost or performance penalty.
- The use of durable and recyclable materials is encouraged.
- Use of plantation, recycled or composite timbers and avoidance of all unsustainably harvested exotic timbers is encouraged.
- The design team is required to submit a waste management plan for both the construction (including any demolition) and ongoing operation of the building as part of the Final Sketch Plans.
Internal finishes are to be chosen that minimise the release of Volatile Organic Compounds (VOCs). Many common materials such as paints, glues, laminates and fibreboard contain VOCs that are released into a building and have an adverse impact on indoor air quality. This can lead to reduced productivity and health problems for occupants. In many cases a suitable low VOC product can be chosen with little, if any, cost premium.
The ANU wishes to encourage staff to minimise the use of cars to travel to and from work. Many staff that choose to cycle to work will only do so if there are suitable facilities available for them to store their bicycle and to change clothes. Initial surveys at ANU indicate that up to 15% of staff cycle to work. Determining specific building needs should be undertaken in consultation with the building user.
The following requirements aim to provide infrastructure that encourages staff cycling:
- Sufficient bicycle storage shall be provided for the building population that provides weather protection, security and ease of access.
- Adequate clearance will be provided around bicycle storage for bicycle movement and pedestrian access.
- Bicycle racks will allow securing with different locking systems (eg U locks).
The ANU is also serviced with some ACTION Bus services so any road alteration involved in building construction should not obstruct large bus movement.
Facilities and Services
8 January 2003