Built in 1961 and expanded in 1974, the New Apostolic Church was structurally sound but lacked any aesthetic appeal. The "Iller 21" project began with the goal of creating a comfortable living space for a family beneath its ten-meter-high tent-like roof.

Initial considerations revealed that the adjacent low-rise building could be effectively redesigned through some modifications to the floor plan and a new entrance.

The design of the living space was developed through numerous sketches, models, and extensive discussions with the clients.

From the new entrance, one's gaze sweeps through the hallway into the living room and the northern bay window. Like a framed picture, the window offers a view of the orchard and a wooden farm shed. This shed, typical of the region, served as the inspiration for the new wooden facade.

The heart of family life is located beneath the high tent roof. A "kitchen box," open to the living space with a counter, was positioned against the eastern windows. The upper level of the box, created beneath the high roof, is accessed via a shelving staircase and a slender bridge.

In contrast to the spaciousness of the interior, the design is deliberately simple and straightforward. The brick walls are finished with a rose-colored lime plaster, allowing the brickwork texture to remain visible. A smooth cement screed floor covers the entire floor. Only the bedrooms and children's rooms feature oiled industrial parquet flooring. The interior doors are made of untreated softwood panels, held in place by two gray-painted vertical L-shaped steel frames with visible hinges.

The project is complemented by a renewable and largely self-sufficient energy concept. A geothermal heat pump with four bored piles in the garden generates heat for the underfloor heating. The heat pump is powered by a photovoltaic system on the flat roof, which also stores the energy in a battery. The pump allows the rooms to be gently cooled in summer using cool water from the geothermal boreholes. This recharges the geothermal storage system for winter. A room-air-independent, automatically controlled pellet stove in the living room can create a cozy atmosphere on cool autumn evenings.