A house with no bills

In 1996, during a three-month renovation of the kitchen and bathroom in my 1894 terrace house in Chippendale, NSW, I disconnected the property from town sewer and water; and installed solar panels and a sewage recycling system. This might not sound remarkable to readers who are off-grid in regional areas, but my house is in the heart of urban Sydney.

No rain or sewage has left the 150 square metre site, of which about 100 square metres has the house on it. The remainder has concrete tanks under a deck, a garden with a curry leaf tree, kumquat, fig tree, tomatoes, lemon grass and basil, and a chook run outside the kitchen, which makes dealing with food scraps very easy.

About 2.5 million litres of rainwater and sewage have been kept here with the help of clay lenses in the soil. The land has mostly been restored to its natural pre-development state when most water stayed on site.

Anyone can do this

The materials we’ve used can be bought at local hardware stores and installed by local plumbers and electricians. We didn’t have to change our lifestyle – our two kids who were six and ten back then adapted easily as everything was simple. Any of us can do this wherever we live.

The most difficult thing then and now is not the plumbing and construction, but getting approvals, especially from councils claiming to be ‘sustainable’. Consultants are also mostly unaware of simple solutions that are typically found on farmhouses in the country.

My approach to council approvals was not conventional, but it worked. Here’s how I recommend you go about it: give the council and any state agency the words of the conditions and approval you wish them to make, then take those to the elected councillors who have different incentives from the staff. Ask the councillor(s) to visit your house and support your project – they are often motivated to be re-elected and tend to support citizens. Staff members may have different, and sometimes negative, incentives – they may be afraid of making mistakes and prefer saying no to taking what they see as a risk (due mainly to poor university and industry ‘education’) because it’s new or might fail, and they may be blamed.

How does the house work?

Rainwater is used for cooking, drinking and showers. Recycled and purified sewage water is used to flush toilets, wash clothes and hose the garden (most houses use about half their water for these practices). Instead of the typical daily average of about 180 litres per person, our house uses an average of just 50 litres per person – just 200 litres for my whole family and not much more than a single person in most homes. In turn, the amount of overflow from the sewage tank is about equal to the amount of wastewater – about 200 litres a day.

U-shaped gutters are silly fire-starters and open to pollution, leaves and bird muck. Our self-cleaning gutters have not been cleaned in 27 years. Rainwater and sewage water tests conducted onsite showed both were cleaner than town water.

Overflow from the 10,000 litre underground concrete rain tank flows to an adjacent leaky well. The well walls are of recycled rocks and sandstone, laid without cement or concrete. As water rises in the well from the overflowing rain tank it flows sideways through the ungrouted gaps and seeps underground. A 150mm deep permanent water basin in the well provides a habitat for frogs – and mosquitoes, the larvae of which the frogs eat.

Solar panels provide electricity and hot water. In 2015, the price of batteries had become affordable and the house was disconnected from electricity. The gas was disconnected in 2022 mainly because a new invention – the air fryer – making baking, roasting and frying quicker, cleaner and cheaper. The house uses about four kilowatts a day and has battery storage for an east coast low, lasting about four days without sun. The off-grid cost was $48,000 in 1996. There are no water, sewage or energy bills (including no fixed charges).

The house connects me more intimately with the sun, the rain, the wind and the earth. It fills me with gratitude, brings me comfort and renews me.

Written by Michael Mobbs, gardener, designer and author.