400–450mm thick stabilised rammed earth with an XPS foam core — achieving up to R4.3 with no thermal bridging. One of the first systems of its kind in Australia.
Developed at Clifton Beach — 2005Our insulated rammed earth system places a rigid XPS foam board at the centre of the wall during construction — fully encased in stabilised earth on both sides. The result is a wall with the aesthetic of natural rammed earth and the thermal performance of a well-insulated modern build.
We were one of the first companies in Australia to develop and build this system in 2005 — and it has been refined over 20 years of Tasmanian projects since.
We supply full engineering drawings for insulated walls and lintels, and the system features no thermal bridging around windows — a common weakness in other approaches.
Our system eliminates thermal bridging at windows and lintels — a common failure point in other insulated wall systems. We supply detailed engineering drawings for every opening.
We provide complete engineering drawings for insulated walls and lintels — ready for your building surveyor and structural engineer. This simplifies the permit process considerably.
The insulated system looks identical to standard rammed earth from the outside — the same characteristic strata layers and natural earth tones. The foam core is invisible once the wall is complete.
Insulated rammed earth walls make achieving a 6 star energy rating straightforward in most Tasmanian climates, even for south-facing or heavily shaded buildings.
Unlike lightweight insulated systems, rammed earth retains significant thermal mass on both faces of the foam core — continuing to stabilise indoor temperatures through the day and night.
We developed this system in 2005 and have been refining it ever since. Chris has lived in an insulated rammed earth home at Clifton Beach for 20 years — the system is proven.
The R-value measures thermal resistance — the higher the number, the better the insulation. Our insulated system starts at R2.49 with a 50mm core and reaches R4.3 with a 100mm core in a 450mm wall.
But R-value alone doesn't tell the full story for rammed earth. The thermal mass of the earth on both sides of the core continues to absorb and release heat over 12+ hours — an effect that standard energy rating software doesn't fully capture.
Clients don't necessarily need to spend extra on insulated walls. With good design, north-facing orientation and quality glazing, standard 300mm walls can achieve 6 stars. We'll help you work out what's right for your specific site.
I built my insulated rammed earth house at Clifton Beach in 2005 and have lived in it for 20 years. The difference compared to my previous standard rammed earth home is noticeable — but so is the cost. We'll help you decide which system is right for your site.
Chris Westcott · Owner, Rammed Earth Tasmania · Building since 1992