Beyond the Hemp House: Exploring potential for the deployment of hempcrete in Aotearoa’s medium-density housing

Aotearoa New Zealand is in the grasp of dual housing and climate crises. According to the Intergovernmental Panel on Climate Change (2023) Assessment Report, it is imperative that we reduce emissions by up to 50% in the next seven years.

Hempcrete is a bio-aggregate construction material derived from the fibre of industrial hemp plants, and typically mixed with a mineral-based binder. At the time of writing, most if not all hempcrete buildings in NZ are single-detached houses. This thesis explores the potential of hempcrete as a tool to radically redefine the future of sustainable housing in NZ, focussing on medium-density housing typologies, rather than the idealised single-detached dwelling.

Broad research is conducted on hempcrete’s performance, feasibility, socio-political uptake barriers, and NZ’s current and shifting building practices and regulations. Additionally, qualitative data on peoples' perceptions of hempcrete as a visible material in the home is generated through a participatory research exhibition. A hands-on exploratory making process generates a range of hempcrete samples for the exhibition, for participants to interact with. Subsequently, the applicability of hempcrete in current NZ medium-density housing is tested, through an exercise of re-developing an existing three-storey building design, adopting a hempcrete structural insulated panel system. The combined research outcomes contextualise and demonstrate the valuable role that hempcrete can play in a future low-carbon, healthy and climate-resilient housing stock for NZ.