De Warren is a communal housing project and living lab in Centrumeiland, Amsterdam. It exemplifies circular design principles and sustainable living, focusing on bio-based materials and community-focused living. De Warren integrates reclaimed materials, renewable energy systems, and a nature-inclusive design, significantly reducing carbon emissions and environmental impact.

Sourcing, testing, and repurposing materials like timber from fender systems and mooring posts introduced risks related to structural integrity, fire safety certification, and processing costs.

Finding a contractor willing to embrace the experimental nature of the project was difficult, as contractors were wary of risks associated with material reuse, high costs, and the intense housing market.

Incorporating advanced technologies, such as geothermal heat systems and parametric modelling, added complexity to the design and construction process.

Besides, the design had to foster communal living while balancing affordability, sustainability, and social inclusivity.

The project includes 16 social and 20 mid-rent homes, with 30% of the space dedicated to communal areas.

Repurposed and biobased materials were predominantly used. De Warren repurposed wood for exterior cladding, balconies, and retaining walls.

The building features energy piles for geothermal heating and cooling, and photovoltaic panels for renewable energy. The building's nature-inclusive design further enhances sustainability by integrating features to support biodiversity (façade gaps for bats, wooden cladding for bird nests, green rooftop to attract insects and birds)

The cooperative emphasised shared facilities, including kitchens, bathrooms, and semi-public spaces. Shared tools, cars, and spaces encouraged a “sharing economy” approach.

Summum Engineering developed parametric modelling tools to design and optimise using irregular reclaimed materials efficiently. The corporation partnered with ToekomstGroep, a contractor experienced in sustainable construction.

The project sequestered over 300 tons of CO2 by using approximately 330 cubic meters of reclaimed wood, reducing the demand for virgin materials.

By overcoming challenges in material reuse, the project demonstrated the viability of circular construction practices. Tools like parametric modelling and partnerships with innovative contractors showed how to optimise reclaimed materials and cut costs effectively.

In parallel, nature-inclusive features created habitats for local wildlife and improved stormwater management, contributing to a healthier urban ecosystem.

From a more social perspective, shared spaces and facilities strengthened community bonds, reduced individual resource consumption, and exemplified the "access over ownership" model.

Winning the 2023 Amsterdam Architecture Prize highlighted De Warren as a model for sustainable and affordable urban living, encouraging other developers to adopt similar methods.