Hemp Building Association
New Zealand (HBANZ)

Our intention is that you will be able to find the answers here to most of the basic questions about building with hemp you may have, and specifically to questions you may have about building with hemp in New Zealand.

Photo credit: Designer: Tracy Graham (Connected Designs), Builder: Nick Sowden (Sowden Building Solutions)

HBANZ:
Promoting & Supporting Hemp Construction

HBANZ believes that starting in 2021, there is going to be a significant increase in the number of hemp homes (and commercial buildings) being built here.
Once people find out about the actual possibility of building with hemp, and then about all the benefits it creates (for the home occupier and for the planet) people usually ask: “So why aren’t there more houses being built from hemp?!”

Access to land? Able to grow?​

If you have access to land where you could grow your own hemp, you could potentially use the hurd from that crop to build your own hemp house (or retrofit an existing house). This is because you will be able to get your crop processed at the decortication plant in Christchurch – NZ Natural Fibres

Although this maybe a challenge if you are north island based (in terms of transportation of material to and from the decortication factory in Christchurch), it is till preferable to importing your hurd from overseas.

Because hemp is classified taxonomically as Cannabis sativa, New Zealand’s hemp cultivation is regulated by the Ministry of Health.

Farmers/growers who want to work with cultivate hemp must first obtain licenses from the Ministry of Health. Industrial Hemp Licensing Application Guide is located  online here.

Producers are only allowed to sow seed varieties which are on the approved cultivar list, also found on the Ministry of Health website – view here. 

Why do we have so few hemp houses in New Zealand so far?

New Zealand currently has only a small number of hempcrete homes. However there are a large number in the planning stages, including four hempcrete eco-villages & subdivisions. There are however currently several more being constructed / planned. (Australia currently has over 160 hemp houses – so we have a lot of catching up to do!)

NZ’s first commercial decortication factory

One of the reasons for the small number of hempcrete homes so far is that here in New Zealand we have not had a decortication plant (ie – a hemp fibre processing factory). This has meant that anyone considering building with hemp has had to import the hemp hurd (the inner part of the stalk that we build from) in from Australia or even Europe. In terms of carbon footprint, financial cost and logistics, this necessary import of hurd has been challenging. However, Hemp New Zealand, Carrfields and NZ Natural Fibres have together invested in and opened a decortication break-line plant in Christchurch in late 2021. This means that New Zealanders can now buy locally grown and processed hemp hurds for construction. We will be able to buy the hurd (sometimes called shiv) which is the inner stalk. This is what we build from. We will also be to buy NZ hemp bast fibre (the outer stalk) which can be made into a huge number of products. The opening of the decortication factory in Christchurch – New Zealand Natural Fibres is a game-changer for the newly emerging New Zealand hemp construction industry.

Hempcrete Homes can be carbon negative.

We’re in a bind…

A second reason for the limited number of hemp houses in NZ so far, has been that the binder for the hempcrete (ie the second main component of the hempcrete) has had to be imported from Australia or Europe.

The binder is generally made from lime (hydrated lime and usually also with hydraulic lime and / or clay). We currently do not have a certified hempcrete binder being produced in NZ and so we still have to import it. This is especially the case for commercial hempcrete builders in NZ who want the certainty of using a certified performance known product. This is less of an issue for those folks wanting to do their own smaller builds of sleepouts etc as it is possible to make your own binder.

It is hoped that a NZ produced and certified binder will be being produced and sold commercially in NZ in 2021.

We have included links here to the existing suppliers of binder in Australia, and to NZ Natural Fibres for hemp hurd purchases.