Support for homes built with pre-fab panels of timber and straw
LOS ANGELES: A plan for homes made with straw-filled timber panels has won an international architecture competition, and support for a potential prototype in the Nelson region.
The Kiwi-designed “Strawlines” project took joint first prize in the competition run by London based organisation, INTBAU, (International Network for Traditional Building, Architecture and Urbanism).
Judges said it demonstrated a deep understanding of how local building traditions could be adapted to meet community need.
Project co-designer, Magdalena Garbarczyk, director of Nelson-based company Fineline Architecture, said the Strawlines team were honoured to have been chosen, alongside the creators of a women’s shelter in Africa, from among entries from 21 countries.
”It’s really incredible to be celebrated like this by … people who actually are really mindful of the climate crisis,” Garbarczyk said.
In a project that also addressed the housing shortage, Garbarczyk, architect and researcher Min Hall from Unitec, Institute of Technology, and Fineline’s Mathew Hay, laid out a plan for compact homes that could be put together “a little bit like lego blocks” from prefabricated timber-framed panels containing straw.
Building with straw – the residue from grain crops – instead of burning it would reduce carbon emissions, and help lock away the carbon the plant sequestered, they said.
Up to 40 per cent of the agricultural by-product was burnt in New Zealand each year – enough to produce prefabricated straw panels to build over 2000 houses a year, they said.
The homes would also emit less carbon during construction (embodied carbon) than conventional homes.
The project compared embodied carbon of a Strawlines bedroom and a bedroom in a conventional house, and found a negative carbon result in the Strawlines home (of -1.2 t CO2 equivalent) “effectively functioning as a carbon sink”, compared to the conventional house (at least 8.6 t CO2 equivalent).
Elements of the Strawlines homes could also be assembled offsite, creating less labour and energy.
Fewer carbon emissions would also be created by the homes once they were lived in, thanks largely to the insulating properties of straw and the small size of the 1-3 bedroom properties.
Using the straw and timber panels developed in Hall’s research, “Project Pātūtū”, as part of Strawlines’ housing system, drew on the traditional Māōri practice of building homes with bio-based materials like raupō (bulrush) and endemic grasses.
That compared to the prevailing model of timber framed houses with profiled metal roofing – generally built on reinforced concrete slab foundations, with aluminium windows and doors, and clad with brick veneer, cement boards or imported timber weatherboards.
“Using materials that sequester carbon … is what we are trying to inspire,” Garbarczyk said.
The team hoped to construct some Strawlines buildings that would inspire people with the power to build housing at scale, to collaborate with them.
They had had conversations with interested parties – “the most promising” so far being with Te Āwhina Marae in Motueka, she said.
Twenty new homes were to be built at the marae in the first stage of a $28 million redevelopment project – due to get underway next month.
The homes were to be constructed under the largest papakāinga project Te Puni Kōkiri – Ministry of Māori Development has supported, with an investment of nearly $10m.
“Te Āwhina Marae have expressed a strong interest in collaborating with us, and potentially getting a Strawlines prototype built,” Garbarczy said.
“We are currently in conversations with Te Āwhina Marae about how … [they] can become partners in the wider research.”