Hempcrete House

In Lyonville, Central Victoria, sitting at 740 metres above sea level, this house holds a steady 20°C indoors through sub-zero winters — with minimal heating. It carries a 7.6-star energy rating, and in 2023 it won an Inside Out Sustainability Award.

The clients were a couple downsizing from the city, after a home that did less, not more: warm, earthy, and genuinely small. Their brief centred on solar passive design and a material we hadn't built with before — Hempcrete. It became Altereco's first Hempcrete home.

Our response leaned into "just enough" rather than working against it. The ground floor is just 75m², with a 30m² mezzanine tucked above the kitchen and dining space — 106m² in total, and deliberately so. Every square metre earns its place, nothing more. Hempcrete did a lot of the work. Its 300mm walls resist fire, pests and mould outright, and the lime-and-clay plaster breathes — letting fresh air move through the structure while keeping humidity in check. It's also carbon-negative: it locks away more carbon during its lifecycle than went into making it, one of very few building materials that can claim that. Paired with double-glazed windows, a well-insulated envelope, and a house oriented dead north for winter sun, the result is a home that barely needs the wood heater it has as backup.

The clients built it themselves, with expert guidance on the hempcrete work — a slower process, but one that left them knowing every wall of their own home.

Completed in 2021, this remains one of the clearest proofs we have that a smaller, simpler house can also be the most comfortable one.