In 2025, Dutch startup Coastruction deployed three large-scale Purpose-Built Reefs (PBRs). These structures support coral growth and marine biodiversity. The project combines biomimicry, computational design and large-scale 3D printing. As a result, it shows how advanced fabrication can contribute to ecological restoration.

Designing With Nature As A Guide

Coastruction develops reefs based on site-specific ecological data. The team collaborates closely with marine biologists and local experts. First, they analyse the existing ecosystem, including fish species and coral types. Then, they translate these insights into biomimetic designs that reflect natural reef structures.

Each reef spans approximately 15 m² and reaches 1.7 metres in height. The structures weigh around 1.7 tonnes and consist of modular elements between 20 and 85 kg. As a result, they provide both shelter for marine life and a suitable surface for coral attachment. Moreover, the modular system simplifies transport and underwater assembly.

This approach aligns with the ‘Building with Nature’ philosophy. Instead of resisting natural systems, the design works with them. Consequently, the reefs support both ecological and infrastructural resilience.

Scaling Up Through 3D Printing

A key innovation behind the project is ‘Asterix’, a custom-built powder bed 3D printer. It has a build volume of one cubic metre and enables the production of large, detailed modules. Moreover, the team optimised the print process to increase efficiency and reduce material waste.

Importantly, Coastruction focuses on low-impact material strategies. The reefs are printed using natural or locally sourced materials, such as beach sand or recycled concrete. This reduces transport emissions and lowers the overall carbon footprint. Furthermore, the company aims to make concrete more circular by reusing production waste and recycling existing material streams.

Given that concrete accounts for 4–8% of global CO₂ emissions, these innovations are highly relevant. They demonstrate how designers can rethink conventional materials for more sustainable applications.

From Fabrication to Deployment

After production, the team packed the modules into a single shipping container. This reduced transport volume and improved logistics. Once on site, divers assembled the reefs underwater over several days.

Subsequently, coral fragments were attached to the structures. This step initiated the long-term regeneration process. The reefs now function as a substrate for coral growth and as habitat for fish populations.

Meanwhile, monitoring continues to assess ecological performance. Over time, the project will provide insights into how artificial structures can support natural regeneration.

Material Innovation for Environmental Impact

The PBR project illustrates how material innovation can support environmental goals. It shows how digital fabrication and biomimetic design can work together. For architects, landscape designers and product designers, this offers a clear example of regenerative design in practice.

Meanwhile, monitoring continues to assess coral growth and fish populations. Over time, the reefs will reveal how effective these structures are. Ultimately, the project demonstrates that design can actively contribute to restoring natural systems.

Source: Coastruction
Photos: Coastruction / Eva Beets / Lotte Fonteijne