21-year-old Bachelor of Product Design student Andy (Minhong) Park has developed a biocomposite wall panel that uses algae – or seaweed – as a bio-filler to help the building and construction industries become greener.

Originally hailing from South Korea, Park experimented with the low-cost plasterboard alternative as part of his final year project after identifying the significant environmental impact of the building industry.

“Currently the building industry contributes 20% of New Zealand’s carbon emissions,” Park says. “As the sector faces the challenge of reducing carbon emissions but building more houses, and with plasterboard used in almost every home, seaweed plasterboard offers a viable green alternative.”

The plasterboard has moisture control features and is a low-cost material, helping the building industry reduce its footprint through recyclable components. Compared to traditional gypsum board, seaweed plasterboard requires significantly less energy to manufacture, further reducing its environmental impact.

Damaged or deformed seaweed plasterboard can be ground and used as a fertiliser, so is suitable for both the construction and agriculture industries. Because the plasterboard is made without harmful and non-recyclable ingredients like fibreglass and vermiculite, it is also an environmentally friendly approach to fireproof plasterboard.

“Seaweed is fast-growing at 0.5 metres per day and is capable of sequestering around 173 million metric tons of carbon annually. It’s easy to cultivate and can be farmed offshore, not competing for farmable land with other bio-based materials, making it an attractive, lowcost farming commodity.”

“Because seaweed can absorb carbon underwater, large wall-panel manufacturers could employ seaweed farming as a carbon offset by growing it,” Park adds. Seaweed bio-filler also contributes to warmer, drier, safer homes, and Park says preliminary testing indicates fire performance at the level of commercially available products.

“Seaweed has been proven to reduce ignition risks, increase flame retardancy, and promote auto-extinguishing behaviour of seaweed-based composite systems because it contains boron, a natural fire retardant,” Park says.

“Seaweed is recognised for its ability to absorb and release moisture and is a greener alternative to traditional passive fire protection materials due to the absence of non-recyclable elements. This also makes it able to be recycled and used as a fertiliser.”

The finished seaweed plasterboard product has a glossy marble surface, coloured green, red or brown depending on the type of seaweed used. Park’s eco alternative to traditional plasterboard was recognised in the UC Innovation Jumpstart Greatest Commercial Potential Award and won the accompanying $20,000 prize.

After the success of his 12-week project development plan, Park and his lecturers are in the early stages of a commercialisation plan and are working with Kaiārahi Rangahau Māori to identify suitable species of seaweed for product development and marine agriculture.

Park and his team are calling on additional funding and input from industry experts to assist in further research and business development.