Queenslander retrofit hempcrete home | How to Video

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The main components of the house, the footings, structural framework and roof are all in good condition being structurally sound and of a good size and layout for a family to live and thrive in. But as with many houses built in Australia there was little consideration of thermally controlling the internal areas considering fairly mild weather, cheap power, lax building standards in regards to the thermal envelope (insulation and sealing) and the idea that building was cheap so ‘lets knock up some houses now for people to live in an we’ll deal with anything later’. This means there are 1000’s of houses around Australia with little insulation or proper sealing or other passive design principals regarding shading by eaves and thermal mass. Which means it’s hard to maintain the temperature at a level comfortable for humans in both summer and winter. In summer we crank the aircon and in winter we turn on a few bar heaters and maybe put on a jumper.

A good article about this can be found here. https://www.theguardian.com/commentis…

So what makes this a very important project is that we are using a fantastic framework for a house, and therefore not doing a knock down and re build, so limited new materials need to go into making this house good for another 100 or many more years.

Some internal walls were re arranged to allow for a more open plan style living. The wiring was completely re-done for safety reasons and to bring it inline with modern expectations. Some plumbing was done regarding placement of the kitchen. Upgraded flooring and roofing, including insulation is part of the project.

A deck facing the Western view with an awning to protect from the harsh summer sun will complete an indoor/outdoor forward lifestyle house.

Additionally the experienced and eco conscious owner builder opted for up-cycled doors and windows framed by locally sourced timber. The hemp bast comes from just a few hundred kilometres away (close by Australian standards). The sand and water from the region. The lime binder I am not sure about but I intend to find out!

Hemp grows quickly whilst sucking in CO2. When turned into hempcrete the drying and curing process continues to suck in CO2. And then the hempcrete slowly carbonates to stone over many years so gets harder and harder all whilst sucking in CO2 from the atmosphere. This makes hempcrete a carbon negative building material. Combine a carbon negative building material into a house that is already built and you have a carbon negative family home that is super well insulated so will take very little external power to heat and cool the spaces.

Thats what makes this project very important for everyone on this planet. We can grown the hemp and use it to thermally insulate the 1000s (probably 100s of 1000s) of badly built houses around Australia limiting our need for new materials and fossil fuel power needed to thermally control the internal space of the house.

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