This hempcrete structure may be small, but its architects are hoping its impact will far outweigh its physical size. The project, titled Biobuilding, was created by the emerging architecture studio Lúdika, based in Reykjavik, Iceland, and founded by Anna Karlsdóttir and Jan Dobrowolski.
The architects’ goal? To showcase how site-specific and less conventional building methods and biomaterials can offer better results than the industry’s more typical contemporary responses to construction. In the past, the country has regularly used locally sourced materials, for instance in the traditional Icelandic turf houses, so there is a precedent to build on.
Step inside this hempcrete experiment in Iceland
‘Biobuilding began when we moved from London to Iceland and found a construction industry built on concrete and imports. We set out to learn what it takes to build here with natural, locally available materials,’ the architecture duo explain.
‘Around 80 per cent of buildings here are concrete, and almost all building materials are imported. An opportunity arrived at the same time. Industrial hemp cultivation had been legalised earlier that year, and the first growing trials were successful.’
Karlsdóttir and Dobrowolski started looking at hempcrete – a biocomposite based around the hemp plant – as a construction material and realised that they could make the most out of industrial hemp grown at the island nation’s Sandhóll. They used a family-owned plot in a verdant part of Grímsnes to self-initiate a small building project that would serve as a ‘demonstrator’ for their experiments.
The result is Biobuilding, which they composed together with a team of growers, researchers, engineers and craftspeople. A group of German journeymen craftsmen, passing by on their traditional travels, helped them build it.
Physical feasibility and building completion were not the only goal here. The architects also wanted to follow and study the building’s life post-delivery, to assess and monitor its performance and behaviour.
They did this for two years, conducting a life cycle assessment to show ‘what is possible, and also what stands in the way: current regulations and certification rules are prohibitive and policies need to change,’ they say. ‘To us the building is also a sáluhús, a house for the soul.’
Beyond the hempcrete core, the building uses more locally sourced and specially fabricated components. A collaboration with textile designer Alberte Bojesen resulted in sheets for the internal window screens made of Icelandic seaweed. Glulam beams help support the building, and foundation footings were prefabricated off-site. Solid timber joinery, lime plaster, limewash and wool are included in the build.
‘For the design, we took cue from Japanese teahouses: small, humble and connected to the land. From inside, the views are framed rather than open: low towards the mossy ground and the mountains beyond in one direction and opening up towards a wooded area in the other. Three principles guided it: a light touch on the site, natural and locally sourced materials as far as practical, and honest, unfussy craftsmanship,’ the architects explain.
Biobuilding is set to serve as a valuable case study in working with hempcrete in Iceland and beyond, the architects feel. They will continue to monitor temperature and relative humidity in the small cabin in order to further determine adjustments, challenges and opportunities. Their findings are being set out in a final report for Askur, Iceland’s Housing and Construction Research Fund.