If you’re like every other renovation-obsessed Australian, then you’ll know that this year’s contestants on The Block are building carbon-neutral homes in Daylesford, Victoria.
Don’t worry, we’re just as confused as you are – what actually is a ‘carbon neutral’ house?
Being sustainable in the design, build and operations of a household has become more and more important over the last few years. So important that the Nationwide House Energy Rating System (NatHERs) has passed a new policy that all new builds and significant renovations must have a 7-star energy rating. This brings Aussie homes that little bit closer to becoming carbon neutral or having zero carbon emissions.
Let’s find out how to achieve carbon neutrality in your own home and whether it’s actually worth the time and effort.
What is a carbon-neutral house?
A carbon-neutral house is a home that has zero carbon emissions due to generating as much renewable energy as it consumes. These dwellings are also commonly referred to as ‘carbon zero’ or ‘zero emission’ homes.
Carbon-neutral houses consider the design, construction and resources used to run appliances and fixtures within the home.
How is a carbon neutral home built?
Achieving a carbon neutral home begins from the construction phase. The design of the home, materials used and the construction method are all important factors that can’t be overlooked. If you’re starting from scratch, being carbon neutral can be that much easier. You can use the GreenSpecs guide from Allianz Australia, and look at each room in your architectural plans to see how you can encourage sustainable practices.
As a general model, here are the key features of a carbon-neutral home:
1. Orientation
Before you even begin to think about how you want your new home to look, you have to consider which way it’s facing. The way a house is oriented can determine how much of the natural resources – i.e. the sun, wind, rain – outside can be utilised. The sun can be used for heating and energy purposes (solar panels!), and wind can contribute to those summer breezes that cool down the house. This maximises the overall energy efficiency of a household.
Leveraging the natural elements is something best left to the pros, so collaborating with an architect is the way to go with new builds. They’ll ensure that your design incorporates passive heating and cooling principles.
2. Solar power and sustainable energy sources
Generating your own power is not new to anyone. However, it is still one of the most important factors when it comes to a carbon-neutral home. Solar panels take full advantage of an energy source that is easily accessible and ultimately cheaper to use in the long run.
Better yet, by including battery storage on your property, you can store surplus power for the darker, less sunny months, ensuring you never have to purchase electricity from the grid!
3. Insulation
Keeping your house warm and cool is one of the biggest energy costs. If you start with good insulation, then those costs can drop dramatically. Having high-quality, high thermal insulation not only in your walls but also your flooring and ceiling will cut down how much you’ll need to use things like air conditioners and heaters.
And although it may be more costly, installing double (or even triple) glazed windows means that the outside cold won’t seep in, and additional heating can be limited.
5. Using the garden
Using your garden to enhance your sustainability efforts will not only keep your home carbon-neutral but also give you delicious food to eat. Growing your own vegetables and herbs contributes to the thermal mass of your home and helps regulate indoor temperatures. If you’re planting natives as well, you’re promoting biodiversity and bringing back the local ecosystem.
Having a rainwater tank in your yard can help offset water costs and give you the opportunity to water the garden or wash the car without wasting anything. A garden will also need to be fertilised, which can be done by using your food scraps and making compost. The cycle of sustainability can be started quite easily when you think about it!
6. Energy efficient appliances and fixtures
Having appliances that reduce energy costs is the most obvious way to reduce your carbon footprint. This covers almost every fixture and product you could possibly have in your home, including:
- Solar hot water system or heat pump hot water system
- Low-flush toilets
- LED light bulbs
- Induction cooktops
- High-efficiency star rating white goods; washing machine, dryer, fridge
- Sustainably grown timber flooring
Sustainable fixtures can even move into homewares, such as using natural linens and fibres for carpets and furnishings. Using low-VOC paints will also contribute to becoming more sustainable.
7. Lifestyle
Changes to your lifestyle choices can help bring your carbon footprint down, and get you that much closer to becoming a carbon neutral house. These choices could include:
- Operating your home to improve thermal comfort, without turning on heating and cooling appliances. This can be done by opening windows in summer, closing doors to create heated zones in cold weather and using curtains and other insulating window coverings to preserve heat.
- Reduce water usage: replacing showerheads and taps with water efficient models, taking shorter showers and washing clothes in cold water. This should be old news for anyone that lived through the droughts in the early 2000s!
- Switching to low carbon transport options like walking, cycling and using public transport. If you’re in the market for replacing your car, consider hybrid or electric models, as this will reduce your fossil fuel contributions.
What are the positives of being carbon neutral?
Becoming a carbon neutral household gives you sustainability points – your home is literally as sustainable as it can be (without becoming disastrously expensive). Apart from getting bragging rights and helping save the planet, being carbon neutral has a few positive effects.
Lowers energy bills
A study done in 2019 by the Cooperative Research Centre for Low Carbon Living identified the cost benefits of being carbon neutral. By upgrading pre-existing display homes in Canberra, Melbourne, Perth and Townsville to a net zero energy standard, they reduced annual energy costs by up to 88%. Although building to carbon neutral standards is 6-11% more expensive, lowered energy bills will definitely make up the difference in the long run.
Modelling from Sustainability Victoria indicates that a home built to fit the standard of the Zero Net Carbon Homes program will reduce energy bills by 60-70%, depending on household size and occupancy numbers.
Increased comfort and lifestyle
Carbon-neutral and zero net carbon homes are made with the intention to keep your home the perfect temperature, so additional appliances don’t have to be used.
Comfortable internal temperatures – warm in winter and cool in summer – are ensured when all of the above factors are taken into consideration.
