Is the Triple Bottom Line (‘TBL’ or ‘3BL’) a dry economic principle or is it a useful way of thinking about your home renovation plans?
The TBL, sometimes referred to as the principle ‘People, Planet and Profit’, has been adopted by companies with a motivation for corporate social responsibility. ‘Profit’ or a ‘return on investment’ is measured across three elements – social, environmental and economic. It’s not all just about the most obvious dollars.
Given that the housing sector typically accounts for 20-30% of national energy use, it is important we consider sustainability every time we renovate or build a new home. The Brisbane City Council has also helped set the challenge for us by committing to a 50% reduction of greenhouse emissions from the Brisbane community by 2026.
The ‘triple bottom line’ approach to sustainable housing drives a balanced view of social, environmental and economic design factors.
Social sustainability is about considering others – future owners and other users, neighbours and the broader community. It is about designing for people, different users in different stages of their life – young families, older users or users with varying abilities. Homes should allow for changing lifestyles and lifetime needs and should consider safety and security features. The local community and streetscape should also be considered, ensuring sympathetic development, enhancing the streetscape and community function as well if possible.
Environmental sustainability is about considered and efficient resource use, considering water and waste management and energy use. It is about design to limit future need for high energy control of lighting, heating, cooling and ventilation. It’s about low energy lighting and appliance selection. Passive solar design elements should be considered – orientation, ventilation, insulation, shading and building materials used. Consider the local market for materials where possible.
Economic sustainability means designing to make a house more cost-efficient over time. Selection of long life, low maintenance materials is important. Additional expense during construction should provide for longer term operating cost savings. Getting design and material choices right the first time removes the need to make additional costly changes later. Many contend that installation of solar panels or water tanks will add immediate value to a property.
If the TBL principles are addressed when planning your next renovation project, it should result in a more comfortable, liveable, flexible, safe and secure, accessible and healthy home, which should be more cost effective to live in over time.
The Spring Hill “Enviro-Cottage” Project has tried to address the TBL. Examples of the “Enviro-Cottage” TBL considerations include:
Social sustainability
- Multi-use, modular design suitable for families, professional couples, or people with disabilities, young couples through to families with older more independent children
- Use of local Tuff stone to tie to Spring Hill’s heritage and preservation of the heritage streetscape
- Open front aspect to connect with local street life
- Open design to aid easy internal and external surveillance
- High security features to all doors and windows with simple and consistent locking systems
- The set back garage designed to de-emphasise the role of the car, but the addition of two off-street parking options takes two cars off the crowded local street
Environmental sustainability
- Maximum use of passive solar design aspects, taking advantage of natural energy flows, and minimising the scale of overlaid systems – lighting, cooling etc
- No air conditioning required or other mechanical heating or cooling systems
- Capture, use, recycle and re-use of as much rainwater as possible, inclusion of greywater processing system
- Generation of required energy needs through onsite photovoltaic system and where possible provision of clean renewable energy back to the community
- Use of environmentally preferred materials eg. no use of rainforest or old growth forest products
- Re-use of the existing 1800’s building to reduce consumption of new materials
- Use of materials with a lifespan equivalent to the projected life of the building
- Source local products and materials where possible, minimising energy used to transport materials
Economic sustainability
- Use of passive solar design and selected enviro-products will drive future operating costs down to a minimum
- Modular design, flexible usage model, and choice of long lifespan materials, minimising any requirements for future renovations, minimising ongoing construction costs
Details of the enviro-products selected for use in the Spring Hill “Enviro-Cottage” will soon be included on the project web site at www.envirocottage.com.au. Further detail on triple bottom line principles in respect of Queensland housing can be found at the Sustainable Homes Program website or at the State Government Smart Housing website.
