Sustainability Report

Embodied carbon strategies 

• De Warren’s structure and envelope are defined by extensive use of timber and recycled materials. A total of 330 cubic metres of wood is used across the main supporting structure, facade finishes, wood-frame facade elements, window frames, and interior walls.
• This volume of wood has stored more than 300 tons of CO2, equivalent to approximately 200 years of emissions from the average car in the Netherlands.
• Reclaimed materials form a significant part of the project. Timber was sourced from former fender systems and from azobé retaining walls previously used in marinas. Before installation, the planks were doubled to reach the required thickness and left untreated, resulting in a maintenance-free finish. Basralocus mooring posts were reused to create the “mikado” balcony fronts. 
• Reusing structural and facade materials reduced demand for virgin resources and lowered associated embodied carbon.

Operational emissions strategies 

• De Warren achieves an EPC of -0.16, classifying it as an energy positive building. An EPC below zero indicates that the building generates more energy than it consumes.
• The project does not connect to the local heat network. Instead, heating and cooling are generated on-site using 30-metre energy piles. Hoses installed through the piles act as heat exchangers connected to a heat pump that extracts and distributes ground heat or cooling throughout the building. Electricity production is supported by photovoltaic panels installed across the roof, with a total of 196 panels.
• The project incorporates shared kitchens, bathrooms, and tools, reducing duplication of household resources. Shared cars and semi-public spaces further support resource efficiency.

Reused azobé retaining walls, reclaimed basralocus mooring posts, and timber from fender systems reduce new material requirements. Untreated cladding minimises future maintenance. Azobé and basralocus were selected for their durability and resistance to environmental exposure.