Bushfire resistant and mould-free homes become cheaper to build with Tasmania's first mobile hemp processing unit

The mobile unit allows farmers to value-add their hemp crops, creating profit from waste that would otherwise be burnt, and will cut import costs for those wanting to use the hurd for hempcrete.

Hempcrete is created by mixing hurd, a fibre made from the woody part of the hemp plant stalk, with lime and water, to caues a chemical reaction that turns the mixture into a durable stone.

It is marketed as a healthy, natural and sustainable building material that absorbs carbon from the air, sequestering an estimated 249 kilograms of carbon over 100 years.

Ms Luca, who lost a house in the 2013 Dunalley bushfires, became interested in hempcrete when she discovered that the building material was fire resistant.

"When I was looking at rebuilding I learnt that hempcrete can't catch fire, you can literally put a blow torch to it and it doesn't burn. That is hugely appealing for those that are building in bush-fire prone areas," Ms Lucas said.

"But there are so many benefits to this material. For one thing it is breathable, where it allows moisture to pass through, it is mould resistant, anti-bacterial, has good insulation, and there is evidence of hempcrete homes lasting for a thousand-1000 plus years. This is an incredibly robust material."

When an opportunity to purchase the mobile processing unit to create hurd for hempcrete came to Ms Lucas by chance, as a result of the Covid-19 pandemic, she decided to invest.

"We grow 80 per cent of Australia's hemp in Tassie and have enough raw material here to supply every hempcrete builder in Australia, but at the moment this locally grown hemp material is not being used," she said.

"The head of the hemp plant is taken off for seed and then the tall straw is left in the paddock. The growers let it dry off for a period of time and then they do a control burn to get rid of that waste product.

"It is absolutely bonkers that farmers are losing out on this value-add, wasting time and money on controlled burning. On the other end, people drawn to hempcrete for the environmental aspects are sometimes having to buy from another hemisphere."

Ms Lucas said instead of letting grain stubble go to waste she would be offering growers an opportunity to make extra profit from their hemp crops.

She said the mobile unit contains a processor and separation line inside a 40 foot container that can be moved on a tilt truck to the farm to process on paddock, which can then also be moved to supply hurd for housing and animal bedding.

"We send in a bailing machine after the header, and then we take those bails to be processed [in the mobile unit] and turned into hurd," she said.

"The hurd looks like woodchips, basically a really dry straw of one cm lengths. At the building sites this is poured into a mixer with a binder, and that forms the slurry that is then used for hempcrete."

Ms Lucas said the unit will create high-value hurd for building, a straw for compostable animal bedding, and a mulch.

"At the moment they use sawdust for animal bedding which gives respiratory problems and can't be composted, but hemp straw can be mucked out and composted again."

All products will be available to the local market through her new business X-Hemp, that is set to take advantage of the sustainable lifestyle trend that is booming across Australia.

Ms Lucas said the unit will save local builders from having to import hemp materials from mainland Australia and overseas, which in some instances could save up to $20,000 in transport costs.

She said she already has received high interest in the product.

Ms Lucas, who recently returned to Tasmania from overseas and is now working as the executive officer of the Tasmanian Hemp Association, said the timing for such a venture feels right.

"Covid-happened, investors for the processing unit dropped out. I never thought I would become a hurd manufacturer in 2020. Nothing is normal about this year but I believe the timing for this is right and I'm really excited."