Author Michael Mobbs reflects on what he’s learnt about sustainability over the last 20 years. From living without a car and bringing key services in-house (his home is not connected to mains water, mains electricity or mains drainage) to growing his own food and being careful how he spends his money, Michael considers how effective he has been.

David Winterton from Sydney-based consultancy Ecological Design gives us a rundown of solar photovoltaic (solar PV). We find out how it works, what the key considerations are and why prices of PV panels always seem to be coming down!

Cath Hassell from ech2o consultants explains what rainwater harvesting is, why it’s useful and how to get started.

If you haven’t heard our first podcast interview with Cath on the topic of saving water, check that one out first!

Paul Jennings from ALDAS talks through some of the findings from the airtightness tests we carried out as part of our documentary.

Mark Chesney from Beam Vacuum & Ventilation explains how houses have become increasingly airtight and why this has had a significant impact on energy efficiency. He also shares why having a good ventilation strategy is so important.

John Butler tells the story of how he retrofitted a bungalow to be more energy efficient. Having carried out a lot of the work himself, he also shares what he's learnt about airtightness and overheating.

Jackson Moulding from Ecomotive tells the story of Ashley Vale, a group self build scheme in Bristol, UK, that initially had to fend off a large developer in order to secure a plot of land. The will of the local community was instrumental in making this happen.

David Sharpe from Thomasons explains what the foundations are, why they must be site specific and how they could impact on the design of a building.

James and Dani McDonald reveal why they were drawn to HUF HAUS, how the process worked and why they have become very loyal to the brand.

Alex Baines talks through the plans for his semi earth-sheltered home, to be constructed to Passivhaus standard, and explains why involving the local community in the early stages was essential in gaining the relevant permissions.