Case Study: The Castlemaine home that heats and cools itself

Virtually zero

mechanical heating and cooling needed, all year

North

facing living spaces, aligned with the sun's path

3 jobs

done by every hempcrete wall: insulate, store heat, balance humidity

2 tanks

of water storage, plus a worm farm septic system

Orientation

Designed around the sun

Before a single wall went up, the whole layout was aligned with the sun's natural path across the sky. The main living spaces face north, drinking in maximum winter sun exactly when the home needs warmth most.

Along the southern side, the laundry, bathrooms and study line up to form a thermal buffer: a quiet service spine that shields the living areas from the coldest aspect of the block.

North · winter sun

Living

Dining

Kitchen

Laundry

Bathrooms

Study

South · thermal buffer

Round window punched through the rendered gable, seen from the porch under the deep timber-lined eave, with a timber bench below — Geometry doing the work

Shading

Eaves calculated to the season

The deep, timber-lined overhangs are not just a good look. They are calculated precisely to block the high, hot summer sun before it ever touches the glass, while letting the low winter sun reach deep into the home.

The same discipline shapes every opening, from the full-height glazing on the north face to the round window punched through the gable. Comfort by geometry, not by switchboard.

The wall system

Behind the lime plaster, the walls are the air conditioner.

The home's natural climate control is hidden inside its beautiful lime plastered walls. Hempcrete does three jobs at once, quietly, forever, with no moving parts.

It insulatesGenuine thermal resistance keeps winter warmth in and summer heat out.

It stores heatThe walls bank the day's warmth and release it slowly as the temperature drops.

iii

It breathesRemarkably, hempcrete also regulates indoor humidity at the level best for human occupation.

The quiet systems

Everything else, working in the background

Heat pump hot water

Efficient hot water using a fraction of the energy of a conventional unit.

Hydronic heating

Gentle radiant warmth for the rare cold snap that asks for a top-up.

Cross-flow ventilation

The plan is arranged so breezes wash through and flush summer heat naturally.

Two large water tanks

Substantial rainwater storage for the home and garden.

Worm farm septic

Wastewater treated biologically on site, closing the loop.

Natural lime plaster

Breathable, beautiful finishes that let the hempcrete walls do their work.

Fresh from the shoot

The exterior, in full

The full exterior series from Simon Griffiths' photography session, from the air and on the ground.

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Aerial view of the full home showing the north-facing living wing and wrap-around eave against the surrounding gum trees — The whole home, from above

Corner view of the home showing the round window, entry porch and full length of the north-facing eave — The porch corner

Long view along the north facade, showing the full run of glazing under the deep timber-lined eave — The north face, end to end

Closer aerial view of the porch, round window and gable end, showing how the eave shades the glazing — Where the shading does its work

Interior photography from the same shoot is being finished and will be added here soon.

The home that heats and cools itself