Attention is being cast on the potential of blue biomass building materials – those made from seaweed, seagrass, algae and shell-based minerals. What's even more exciting is that this revolution is starting to move from the lab bench to building sites, widening the bio-based toolkit without using arable land or freshwater.
Designers are looking seawards to the promise of “Blue biomass” – renewable aquatic resources such as seaweeds, algae, seagrasses and shell-derived minerals. Marine-base biogenic materials are moving from niche experiment to organised R&D programs and early products, widening the bio-based toolkit beyond timber and hemp.
Policymakers currently use the term “blue bioeconomy” to describe economic activity that makes products from aquatic biological resources, with recent EU reporting singling out algae and seaweeds as especially promising sectors.
This new horizon matters for construction because marine biomass grows without arable land or freshwater, can be cultivated close to coasts, and stores biogenic carbon as it grows. Closely related “blue carbon” ecosystems – mangroves, tidal marshes and seagrasses – are now recognised for their outsized capacity to sequester carbon in plants and sediments, strengthening the climate logic for responsible marine cultivation and restoration alongside material innovation.
The bridge between university research and practice is strengthening through The Royal Danish Academy’s international network, Building with Blue Biomass. This initiative brings researchers, engineers and architects together to convert marine by-products into viable building components. Australian partners at the University of Queensland and Queensland University of Technology highlight the aim: reduce the footprint of buildings by developing circular, bio-based materials drawn from algae, seagrass and shellfish.
What blue biomass looks like in practice
Seaweeds and microalgae
Kelp and microalgae yield polymers (such as alginates) and fibres that can be cast as films, foams and panels or used as bio-binders in composites. The University of Queensland explains the pathway as: cultivating fast-growing aquatic biomass, processing it into biopolymers and aggregates, then forming interior-grade sheets, acoustic baffles and moulded components. Early studies and reviews chart routes to integrate algae into façades and interior products, with the added potential to generate energy in photobioreactor systems – a reminder that ‘blue’ can be structural, surface and service layer at once.
Seagrass
Beyond living meadows that stabilise coasts, post-storm wrack can be collected and pressed into insulation mats and boards. Research groups within the Blue Biomass network are testing moisture behaviour, fire performance and durability so these low-toxicity boards can be specified with confidence, especially for interiors. The Nordic Blue Building Alliance is in the process of mapping supply-chain steps from cultivation to certified products, pointing to the possibility of procurement frameworks.
Shell-based minerals
Mussel and oyster shells – currently a waste stream for aquaculture – offer calcium-rich feedstocks for limes and cementitious fillers. The Royal Danish Academy frames this as a circular mineral loop: recirculate biogenic carbonates into plasters, terrazzo and composite panels, displacing mined limestone or sand, and locking marine by-products into long-lived building elements.
Chitin and chitosan
Crustacean shells yield chitin; its derivative, chitosan, shows promise as a bio-based fire-retardant coating and additive in wood and bio-composites. Researchers in the network and allied labs are testing char-forming, low-toxicity formulations as alternatives to conventional halogenated chemistries.
Why the ocean now?
Two forces are converging. First, science: the carbon and biodiversity benefits of blue ecosystems are clearer than ever, and national agencies (including Australia’s CSIRO) are quantifying mitigation opportunities to inform policy and investment.
Second, coordination: cross-disciplinary networks – architects with marine scientists, materials engineers with aquaculture – are accelerating this translation into tested, specifiable products. QUT describes the mission succinctly: to unlock research at the interfaces of architecture, materials science and advanced manufacturing so blue biomass can become a mainstream, low-carbon feedstock.
Where construction fits, now and next
The near-term applications for biogenic ocean materials can be found for interior: acoustic panels, wall linings, cabinetry, furniture substrates and insulation – places where thickness is modest, loads are low and clients value non-toxic binders and circular end-of-life pathways. As moisture control, stiffness and fire strategies improve, these materials can move into more demanding assemblies. The story is incremental: multiple marine-derived ingredients, each doing what it does best, assembled into compelling interiors that store carbon and divert waste.
This report by Arup explains the potential for blue biomass materials
Blue biomass does not replace bio-materials, it complements them, expanding regional options while easing pressure on farmland and freshwater. The next iteration of new material development is exploring kelp, seagrass and shells – proof that climate-positive materials can be grown in saltwater and designed into everyday buildings. For a sector hungry for credible reductions, that feels less like a trend and more like a tide change.
Further reading
- How renewable marine blue biomass can reduce carbon (UQ)
- Royal Danish Academy – Building With Blue Biomass network
- Blue Carbon with CSIRO
- How can blue biomass contribute to a more sustainable built environment (Cambridge University)
- Algae-powered buildings: A review of an innovative and sustainable approach to building (Sustainability Journal)
- EU Blue Economy report
