We are often asked what it means to build "Carbon Zero' ...how can we actually build in a way that reflects on the amount of energy that is used to construct and operate our buildings ? The answer is not that simple, and you to ask yourself some questions before getting the sketching started...
Consider if you are aiming for 'zero carbon' from energy and waste generated during the construction process, from the construction process and for the life of the building, or if you want to also take into account the energy used during the eventual demolition of your building.
Choose a site/ location that allows for renewable energy opportunities and reduces transportation and food production needs. Many community and environmental focussed developments are now positioning themselves to achieve carbon neutral in terms of energy production and waste treatment.
Maximise passive design strategies:
a. Orientation is key. So where possible try to orient the building with smaller walls facing west and include overhangs and porches.
b. Position various areas/ rooms of a building depending on their heating and cooling requirements.
c. Consider window types depending on elevation e.g. casement windows are best for capturing cool summer breezes.
d. Thermal mass: What are the best location for this ? Should it be located externally or internally as well ? Upstairs or on ground level ?
Decrease building energy requirements:
a. Increase foundation, wall and ceiling insulation.
b. Use low U-value, low-E windows in all climates and low solar heat gain (Low SHGC) windows in cooling climates.
c. Seal all holes, cracks, and penetration through the floor, walls and ceiling to unconditioned spaces.
d. Install adequate ventilation, especially for kitchen and bathroom areas.
e. Increase efficiency of mechanical cooling and heating method.
f. Install efficient lighting and appliances
g.Install automated systems: zoned electrical cut-offs, programmable thermostats, photo-sensitive outdoor light fixtures and / or motion sensors connected to lighting and air conditioning
h. Incorporate renewable energy sources e.g. solar PV and / or wind turbines
Reduce water use in conjunction with reducing the demand for hot water.a. Install efficient fixtures / fittingsb. Solar-boosted gas hot water system (HWS)c. Locate HWS close to outletsd. Rainwater harvestinge. Grey / black water treatment & re-use if allowed by local authority
Select materials / construction methodology that enhance the passive design strategy and have a low embodied energy.
d. Flat pack
Understand the design and Monitor energy and water use
a. Understand the way certain energy efficiency features of the building work
b. Tenant / occupant monitoring and reporting
c. Proper maintenance of equipment and appliances.
That’s a good start, but the above will always change and adapt to the specific requirements of client, brief and budget, not to mention developments in systems that can be incorporated into your design. Further, it is important to not just actively research the latest trends in sustainable design, but forge relationships with expert consultants and contractors who deal with this as their bread and butter – it keeps you looking for better solutions, while making sure these initiatives can be delivered locally and in a cost effective way.
|‘Global Warming Cool It’ by the Australian Greenhouse Office 2007,
|‘Baseline Energy Estimates 2008?, www.nathers.gov.au,
|‘Your Home Technical Manual’ www.yorhome.gov.au