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The house you don’t need to render, plaster, paint or insulate. The house with the building material that you can grow on one hectare (2.5 acres) of land. The same building material you can process yourself with standard machinery available at your hardware store. The house whose walls lock away over 110 kg (240 lb) of carbon per cubic metre.

Impressive claims. What is this boastful house made of? Hemp. The whole hemp. We’ve talked before about hemp bales, and even hempcrete. But this appears to be something new.

Two years ago we wrote about Klara Marosszeky’s ongoing research to produce an easily worked building material based on Australian hemp. At that time she was concentrating her work on the hemp hurd — the pithy centre of the stalk — but that proved too costly to separate from the bast — the tough fibrous sheath of the stalk, in a process known as decortication.

But now it seems Klara has hit on a way to use the whole of the stalk and mix it with lime plaster to create a hemp-based, building masonry material.

When interviewed in the Echo News earlier this year, Klara Marosszeky observed that, “Using hemp masonry to build also means you are using a low embodied energy product because you don’t have to fire them like bricks. You can effectively build a house in four days.”

From what we understand, the hemp/lime mixture is then pressed into formwork, as in-fill between a timber-framed structure. As it hardens it becomes a solid, yet ‘breathable’, insulative, masonry-like wall substrate, such as Klara is leaning against in the next photo.