Sustainable building
Now more than ever, sustainable buildings are needed. We know investors look for location, amenities, and connectivity to transport, but now they’re also looking for energy-efficient infrastructure. Energy efficiency is becoming less optional and more necessary.
The next generation of renters is more demanding of green outcomes, too. Investors all over Australia are now looking more closely at buying properties with solar panels, batteries, and electric vehicle charging to reduce running costs and attract and retain good tenants.
But sustainable buildings are not the Grand Designs mud-brick houses of decades gone by. Here in Australia, we have some of the most innovative, clever, and eye-catching sustainable buildings around. So what makes a building sustainable and how can we rate its effectiveness?
Fossil fuel free
Buildings that use no gas ensure net positive CO2 emissions. Solar generated electricity and hot water make for a fossil fuel free and carbon neutral operation.
In addition, combining PV panels with a metering system and electrical reticulation can provide a building with 100% green power.
Some buildings have even gone so far as to include wind turbines and gardens on their roofs.
Thermal performance
Electricity needs can be significantly reduced with carefully placed windows and smart use of sunlight. Window louvers can shade a building during the summer heat thus eliminating the need for air conditioning.
Rammed earth walls, triple-glazed windows, and high-density insulation in walls, floors, and ceilings, to achieve airtightness, can produce excellent thermal performance.
Using biomimicry, a building can respond to the outdoor conditions by including automatic shutters that open and close at night, as well as respond to the angle of the sun during the day. Combining this with heat recovery ventilation (HRV) can save more than 90% of the energy typically used on ventilation.
Water efficiency
Water efficiency is another key aspect of sustainable buildings. Rainwater harvesting tanks for irrigation and toilets significantly reduce water use.
Hydronic heating is another useful way to use reclaimed water in a building and because this costs nearly nothing to run, you can have it on low all through winter maintaining a comfortable temperature.
Sewage water can also be used after careful filtration for toilet flushing, air conditioning, and garden maintenance.
There are lots of ways to make a building more sustainable and even just adding one or two of these modifications to your building plans can save you money and help the environment, in the long run.
Regulation and green rating tools
The Commercial Building Disclosure (CBD) Program requires office spaces of 1000 square meters or more to have an up-to-date Building Energy Efficiency Certificate (BEEC) which includes a National Australian Built Environment Rating System (NABERS). This is a way of rating the energy efficiency of commercial buildings by comparing them against benchmarks developed using actual building performance data. The NABERS Energy rating on a BEEC includes a star rating and annual building energy consumption and greenhouse gas emission details.
There is also a Nationwide House Energy Rating Scheme (NatHERS). Although, the Australian Capital Territory remains the only place with a current system for mandatory Energy Efficiency Ratings (EER) for houses. New dwellings built in the ACT must have a rating of 4 and existing dwellings must disclose the actual energy performance when offered for sale. Houses can achieve 0 to 6 stars in their rating scheme, with a higher EER being more cost and energy-efficient, using less energy for heating and cooling, and generating lower greenhouse gas emissions.
For some help in navigating the various regulatory and green rating tools, check out this helpful cheat sheet.