In the Dutch town of Best, Kettinghuls has completed the renovation of a local school—IKC De Zevensprong—following the ethos that “the greenest building is the one that already exists.” The project prioritises retention and reuse of the 1970s structure, with only 17% of the original building demolished and 57% of the new floor area achieved through renovation. Approximately 1500 square metres of the existing school were retained and upgraded, significantly reducing material waste and preserving the embodied energy of the original construction.
Form and function
The centre is not a mainstream school in structure—it focuses on children aged 2 to 12 years old, and provides primary education with additional support services. Its approach supports teachers with specialists such as speech therapists, behavioural experts, and youth care professionals to deliver education and care together.
The upgraded centre adds a new, double-height barn-like structure to the existing facilties. It now features two group rooms for day care and playground, four group rooms for lower grades, five group rooms for upper grades, and one for out-of-school care. Additional spaces, such as a gymnasium with changerooms, playground and balconies, complete the complex.
Materials and construction
The architectural objective was to retain as much of the original building as possible, with 1500 square meters of the existing site renovated rather than demolished. A new two-storey building block with ten classrooms was added. This new volume was constructed using a prefabricated timber system with CLT and glulam, enabling efficient off-site manufacturing, reduced construction waste, and improved build precision. The system is also designed for disassembly, allowing structural components to be reused in future cycles and aligning with circular construction principles. This approach replaces conventional high-emission concrete and steel with renewable, carbon-storing timber elements, substantially reducing embodied carbon.
Sustainable and biobased materials are used consistently throughout the project. The primary loadbearing system of the extension is timber, complemented by Fraké wooden facade cladding that has been treated with fire-retardant. Additional timber elements include balcony structures and the outdoor classroom, a demountable ceiling system made of American yellow pine (Shiluvit), eucalyptus timber used for fixed interior elements,and Schilte timber furniture. Interior flooring is made using rubber-based Duracryl liquid linoleum which balances durability with lower environmental impact.
Floorplan
The renovation reimagines the circulation of the school. All utilitarian features have been moved the periphery of the building, transforming the centre into an open communal space that houses a library and play areas. A new timber structure and CLT floor help bring in daylight and add height to this central space. The facade of the original building has been udpated, with the side adjacent to the sports field now a distinct second entrance for the middle and upper grades. The architecture plays with the relation to the fields, with balconies, stairs, bleachers and a slide enhancing its lively character.
Reuse and recycling
The design strategy emphasises reuse at multiple scales. Existing structural components—including parts of the main loadbearing structure, ground floor, foundation, facade, and roof—are retained wherever possible. The landscape design also incorporates reuse, notably by repurposing existing schoolyard tiles to form planting borders. In parallel, demolition materials are selectively harvested for reuse, further reducing waste streams.
Landscaping
Outside, a covered area on the ground floor and a large canopied balcony add new elements to the building. These spaces are used for growing plants, playtime and as outdoor teaching space. The garden—which has a fruit tree, chickens, and vegetable patch—enhances the school’s green appearance, helping support a temperate climate while giving the students an understanding of food and healthy eating. Rainwater is collected from the new building into a large wooden barrel and the repurposed by students for irrigation, further reinforcing the green ambition and holistic educational approach of the school.
