Features and considerations
Environmentally sustainable design is about creating efficient buildings with a low environmental impact.
Environmentally sustainable design (ESD)
Environmentally sustainable design (ESD) can be included in the planning of a new building as well as the refurbishment of an existing building. ESD seeks to minimise waste, reduce energy and water consumption and provide an enhanced indoor environment.
Buildings impose a significant daily load on resources as well as the very significant embodied energy resulting from their construction. Library buildings have vastly improved their incorporation of ESD principles, with some winning national and international awards for sustainability. ESD has evolved from aspiration to legislated mandatory standards.
The National Construction Code (NCC) provides the minimum necessary requirements for safety, health, amenity and sustainability in the design and construction of new buildings, and new building work in existing buildings, throughout Australia. The NCC incorporates all on-site construction requirements into a single code. It covers the Building Code of Australia and the Plumbing Code of Australia and is managed by the Australian Building Codes Board.
The NCC is given legal effect by NSW legislation, which means that any technical requirements in the code are to be satisfied when undertaking building and plumbing works.
Promoting environmentally sustainable design
Libraries throughout the world have been at the forefront of educating their communities on environmentally sustainable design practices.
As publicly funded community buildings, they offer:
- broad-reaching opportunity to experience and promote environmentally sustainable design
- opportunity for the public to experience the high-quality spaces which can be offered by ESD
- opportunity to be a catalyst for environmentally sustainable neighbourhoods, promoting sustainable design in the public and private realm, and sustainable practices in the community.
ESD can become a feature of the library building, highlighting the environmental initiatives as a way of promoting them to the community. Other libraries may seamlessly integrate environmental initiatives into the architecture. ‘Infomatics’ (digital feedback to inhabitants) supports sustainable behaviour via real-time monitoring and feedback. This can include the amount of energy consumed or generated, water collected, amount of oxygen in the air and the amount of carbon dioxide emitted.
Frequently, the additional capital cost associated with ESD practices is minimal and is very favourably compared with whole-of-life costs.
Benefits of environmentally sustainable design
ESD provides a range of additional benefits beyond reducing a library’s impact on the environment, which include:
- improved whole-of-life and running costs
- healthier buildings including improved indoor air quality
- a heightened sense of morale and well being
- better productivity and concentration
- lower absenteeism
- greater value for assets and demonstration of responsible asset management
- enhanced profile, marketability
- competitive advantage
potential ability to attract funding and grants.
Heating, cooling and ventilation
In most localities in New South Wales the range of external conditions will require public library buildings to be air conditioned for the comfort of users and for the conservation of library materials, however there are a range of initiatives which can augment the requirements for air conditioning.
- the provision of fresh air to the building when the air is cool, such as night purge or mixed mode
- tempering the air through thermal mass, such as thermal labyrinths where the air passes through cool, usually underground, space reducing its temperature before being conditioned
- energy-efficient air conditioning systems, such as Variable Air Volume (VAV) systems, displacement (offering cool air only where needed), passive and active chilled beams (passing chilled fluid through ceiling units), occupant sensoring for Carbon Dioxide levels (monitoring provision of fresh air), geothermal air conditioning, cogeneration and trigeneration (where waste energy in the form of heat is used).
The design should aim to minimise the use of energy from non-renewable resources. Wherever possible it should consider local sources of renewable energy such as solar, geothermal and wind.
Minimal and responsible use of resources
To reduce the ecological footprint, the selection of structural materials and finishes should be undertaken to maximise the use of ecologically sound materials, such as those from renewable and recycled sources and those with lower embodied energy.
The building should reduce the amount of power consumed and can even contribute to energy production. The following are issues to consider:
- the reuse of buildings – while many old buildings may not be appropriate for a contemporary library, renovation could be considered as an option
- new buildings, and refurbished buildings where possible, should provide the flexibility to adapt over time
- materials which capture carbon, such as plantation timber and bamboo products, can be used
- reducing quantum of materials using self-finished materials, considering if a ceiling is necessary under a slab or if the structure could perform as the final finish
- green-accredited materials
- products low in volatile organic compounds (VOC), which are commonly found in materials such as paints, polyurethanes, particle board, adhesives - reducing VOCs will provide a much healthier indoor environment
- recycled building materials – if possible, reuse materials from buildings to be demolished, source recycled materials or choose products which contain a portion of recycled material
- reduce use of medium density fibreboard (MDF) due to noxious formaldehyde glues utilised in production
- insulation with green products, such as natural wool products instead of fibreglass - insulation generally significantly increases the building’s thermal performance
- energy reduction is pivotal to many ESD measures included in building design and construction methods and long-term building operations including embodied energy, recycling, local sourcing, energy efficient lighting and air conditioning
- energy generation, including photovoltaic solar panels, heat exchange, cogeneration, trigeneration, solar hot water and wind power
- be aware of the embodied energy associated with specified materials – the energy required to construct a building, including production and transport of materials, e.g. aluminium, is very high. Seek advice on the value of specifying a material over the longer term from the building design consultant team. Embodied energy, during the construction phase, will be the greatest proportion of energy use in the lifecycle of a building.
There are few functions within a contemporary library which cannot be naturally illuminated, particularly with good thermal and indirect lighting design and UV rated glass. The benefits of natural daylight include:
- lower energy use and costs: more natural light means less artificial lighting
- greater comfort levels: natural light is associated with higher levels of comfort and improvements in productivity
- healthier built environment: natural daylight contributes significantly to the prevention of the ‘sick building syndrome’ which is found in old buildings with poor natural lighting and air quality
- thermal comfort: when carefully designed direct natural daylight can assist in warming buildings in winter
- indoor planting: natural light can promote the growth of indoor plants which improve indoor air quality and increase oxygen levels.
Clever integration of natural light is not restricted to windows. Skylights and clerestories can bring natural light deep into the building. Voids between levels can introduce light to lower levels and internal courtyards can bring both light and additional outlook to deep building footprints.
The extent of glazing will, in part, be controlled by the National Construction Code, which assesses both the heat gain and loss contributed by windows.
A range of performance glass products, which control the properties of shading and heat transmission of the glass, as well as double glazing and double skin facades can resolve many of the issues traditionally associated with glass. External shading devices are an excellent solution for controlling heat gain and direct sun access.
The benefits of natural lighting are obvious, but natural lighting provision to libraries should be designed with care to avoid:
- solar heat gain: especially as a result of large expanses of unshaded glass on north, east and west facades, which will cause increased air conditioning energy costs and discomfort for occupants
- glare: which will cause discomfort to users. Even within newly constructed libraries, which embrace ESD, there have been issues of glare which have involved the retrofitting of blinds and shades
- light sensitive collections and activities: the placement of functions and activities, which by nature must avoid natural daylight, need to be considered including rare books, special collections, artworks and walls allocated for projection.
Ultimately, the design should aim to work with the natural climate factors, and energy sources, in particular solar access and summer shade.
Lighting technology is constantly changing with an aim to create better quality light sources and/or reduce the energy consumed. As a public environment, a library can act as a showcase for emerging technologies.
The use of more efficient lighting design, lighting control and technologies should be utilised to reduce the energy consumption of the building and provide a positive example to the surrounding community of how lighting energy can be used in a careful manner.
Many offices and public buildings have become more sustainable with the introduction of recycling systems. Recycling systems exist in both passive and non-passive forms.
- space for recycling of paper products, glass and plastics
- reductions of non-recyclable waste through purchasing regimes, and
- furniture and fittings which can be recycled or easily serviced/reupholstered.
Sustainable water use
Potential exists for significant reductions in both water use and higher levels of water recycling. In both existing and new library buildings, water savings are relatively easy to achieve and have the benefit of higher cost savings over the lifetime of the building. In existing libraries, everyday efficiencies can be improved through:
- regular inspection and monitoring of leaks
- installation of water efficient fixtures
- post-fitting of rainwater collection (and in some cases grey water)
- upgrades to air conditioning chillers and cooling towers, which account for about one third of water use in public and office buildings.
In new libraries, water consumption can be reduced by:
- specifying water efficient taps, toilets, urinals and showerheads
- choosing water efficient air conditioning systems
- installing a rainwater collection system
- implementing onsite stormwater detention strategies
- considering opportunities to recycle grey water, stormwater and wastewater, and
- asking your architect/landscape architects about innovative solutions such as green roofs and swales.
A holistic approach
Many of the areas discussed above are interrelated as sustainable design principles and must be embodied in a holistic response of the building to its environment. It is commonplace to have an environmental engineer as part of the consultancy team, who will guide the project’s initiatives. Many local councils have policies and procedures relating to ecological sustainability.
The Green Star
The Green Building Council of Australia is an independent, non-government body which promotes and recognises green building practices. Green Star is a voluntary national environmental rating system that evaluates the sustainable design, construction and operation of buildings.