Kromme Rijn College

Our client, SPO Utrecht, in collaboration with the Municipality of Utrecht and following research by the Mrs. Meijer Foundation, decided to renovate the building and add a new extension, making it suitable as the new location for Kromme Rijn College (KRC).

The aim of KRC is to enable students with internalizing behavioral needs to transition within a maximum of three to four years to the highest attainable level of mainstream secondary education in a suitable educational setting.

From an educational perspective, it was considered desirable to organise the school into three distinct clusters: low-stimulus, reduced-stimulus and stimulus-ready. This organisation is reflected in the three floors of the existing building. Supervision and safety are enhanced by locating facilities directly within or adjacent to the group learning spaces. This is particularly important in the low-stimulus and reduced-stimulus clusters, where, for example, lockers are located within the classroom area and toilet facilities are nearby. These clusters also include quiet rooms where students can temporarily withdraw when needed.

In the stimulus-ready cluster, students are prepared for greater independence and collaboration with peers in a more dynamic learning environment. Facilities such as toilets, cloakrooms, the workshop, and the science classroom are located further away from the group learning spaces.

Renovation
We have preserved the qualities of the existing building wherever possible and restored those that had been lost. The generous ceiling heights, wide corridors, granite staircase, and robust concrete structural frame continue to define the building’s identity. A new layout has been designed for the existing building that fits naturally within its original structure. The corridor spaces retain their monumental character, free from exposed building services. The ceilings are recessed between the concrete beams, allowing the concrete structure to remain clearly visible and tangible throughout the interior.

Although the building is not a listed monument, it is fully in keeping with the character of the Kromme Rijn neighborhood: a modern post-war reconstruction district featuring pre-war villas set within a distinctive green landscape.

By renovating the building with respect for its original qualities and complementing it with a contemporary extension, we not only preserve the memory and identity of the neighborhood but also provide it with a renewed sense of vitality for the future.

New Extension
A robust new volume has been added alongside the existing building to accommodate the extension. By assigning it a highly specific programme—including educational spaces with changing rooms on the ground floor, a sports hall on the upper level, and a dedicated outdoor area—the extension is conceived as an independent volume that is carefully positioned next to the original building. The setbacks and roof terrace create a considerate transition to the gardens of the neighbouring houses. As a whole, the ensemble forms both a fitting termination of the row of buildings along the main road and a welcoming entrance to the adjacent Kromme Rijn Park.

The concrete bands, the distinctive arrangement of the steel window frames, and the interplay of open and closed façade elements in the existing building served as inspiration for the design of the new façade. The plinth of the extension is constructed in light yellow brick. Openings in the façade correspond to the height of the plinth, creating a rhythmic composition of solid and void.

To avoid expressing the sports hall directly as a single large volume on the façade, an additional horizontal façade band has been introduced. This visually reduces the scale of the building and allows the roof terrace to be enclosed by a solid parapet. The two façade bands above the plinth each have their own distinct composition, finished in open timber cladding that echoes the rhythm of the existing window frames. The folded façade surfaces create a dynamic architectural expression, enhancing the slender appearance of the volume while producing a rich play of light and shadow in place of the horizontal concrete bands.

Sustainability
The greatest environmental benefit has been achieved through the preservation and reuse of the existing building. This has resulted in significant savings in materials, waste, and CO₂ emissions. In addition, the school has been upgraded to operate at an almost energy-neutral level.

The existing concrete structure has been insulated from the inside and fitted with new aluminium renovation-profile window frames with triple glazing. The distinctive profiled concrete roof edge has been preserved, while a recessed new roof edge has been designed to allow the roof to be insulated from above. At the façade, the concrete floor slabs continue through the façade line, creating thermal bridges. To compensate for this, a strip of electric underfloor heating has been incorporated along the perimeter of the floor.

The building has a high level of airtightness and is equipped with an Energy Storage System (ESS). Measures have also been implemented to enhance biodiversity and climate resilience, including integrated nesting boxes in the façades and on-site rainwater retention. Newly installed projecting sunshades restore the building’s familiar appearance within the neighbourhood.

Art
The exterior façade features an artwork by Esmee Seebregts. Composed of approximately 430 coloured “bricks,” the installation symbolises the different sensory stimulus domains and the connection with the Kromme Rijn area. The bricks are made from recycled plastic mounted on solid acrylic.

The intensity of the colours—and with it the sensory experience—is clearly expressed. The thickened bricks create a fascinating interplay of light and reflections, producing an ever-changing appearance throughout the day. This constant transformation reflects the varying ways in which the students themselves may experience their environment.