In 2009, on the initiative of Bishop Santier, the diocesan association of Créteil, supported by the Chantiers du Cardinal, opted for an ambitious project to expand the cathedral of Notre- Dame de Créteil. Conceived by Charles-Gustave Stoskopf, holder of the Prix de Rome, this architecture is typical of the 1970s when “the theology of blending-in” prevailed at the time. It is part of the contemporary heritage of the City of Créteil. The commission was to double the capacity of the cathedral and to enhance its visibility towards the city. More than a renovation, this project involved a major redevelopment of the cathedral, giving it a new architectural lease on life from a symbolic and pastoral point of view. The new cathedral is anchored in a multicultural city, which includes five Catholic churches, ten synagogues, a mosque, a Protestant church, four Evangelical churches, a Buddhist temple and a Bahai assembly. A dialogue between two different architectural styles, yet consistent, is established. The dome pointing skywards is based on the footprint of the original cathedral. The silhouette of the entrance, on a human scale, is now joined with the monumental proportions of the new project, focusing on the nave of the cathedral that extends from two spherical wood-clad hulls, like two hands joined in prayer that meet above the altar. Large gatherings can be held in this new space.

The existing sanctuary has been remodeled and the benches are placed in a broad semicircle. In daylight, the stained-glass window located at the junction of the two hulls shed a colored light onto the sanctuary, while at night, illuminated from inside, they become the symbol of a living Christian community. The steeple, detached from the building on the corner of the forecourt, marks the cathedral entrance with its slender silhouette, punctuated by three bells from the old campanile. It restores the building urban scale and become a sign in the city beside the large residential buildings of the neighborhood. The view onto the cathedral forecourt is freed by opening the curtain of trees. The new square, built by the city on the opposite side, is an amenity for local residents, and an extension of parish life. 3

An RGB study in light, this sacred space is designed as a coloured glass arch intersected by two shell-shaped spatial forms. Beams of douglas fir interrupt the continuous ribbon of glass by noted stained glass artists Udo and Pascale Zembok. The stained glass gives off a unique effect created by the three colour constituents of light being red, green and blue, which here represent the trinity. Colours evolve, beginning with blue-green colours at the Eastern base and rising up to turquoise green shades on the border with the zenith area. The Western base is tinted in blue-violet tones, shading towards the interface with red-violet at the zenith.

More from the artists: The architectural concept of two intersecting shellshaped spatial forms celebrate a space which unfolds like a border along the interface of the two volumes. This space, designed as a glass arch, is the field of play for this commission. Spatially, the semi-circular arc opens up from east to west. As the only source of natural light the arc culminates at the zenith, vertically centred over the altar. At regular intervals, crosssection wooden ribs interrupt the continuous ribbon of glass.

Our artistic response to the given architectural shape is based on the idea that the incident sunlight artistically metamorphoses and thus should enter equally „sublimated“ into the sacred space.

Paradoxically, however, light itself is invisible, because it is only perceptible to our senses when it reflects on material or flows through filters.

Since Newton proved through his experiments with a prism that the components of light appear as colours, today three colours: red, green, and blue, describe the primary colours of light. When rays of light in these colours are bundled and mixed - an optical additive mixing - then the result is „invisible“ light, or if this is projected onto a surface, a „white“ light. Our design interprets this physical optic law of additive colour mixing for the specific positioning of the glass arch and corresponds to the geo-spatial orientation of the building

According to our analysis, the architectural specification required an artistic response, which can be read in the length of 55meters of the arch as a unity.

Our proposal therefore used only the medium of colour as a means of expression; any form is reduced to a minimum.

Thus our colours evolve, starting from two basis points: ascending from the East and from the West two strands of colour culminate at the zenith. The point beginning in the East starts at the base with blue-green colours and rises up to turquoisegreen shades on the border with the zenith area.

The Western base is in blue-violet tones, shading toward the interface with red-violet at the zenith. This red part of the arch shades eastwards to red-violet and towards the West to red-orange hues.

The simplicity of the concept and composition opens up a range of different levels of understanding for the observant visitor. The spectrum ranges from our delight in chromatic filtered colours and their effects on the interior architecture of the cathedral, to the concept of the three primary colours of light, their spatial positions and the symbolism of the Holy Trinity.

The language of colour is left free; the individual mental attitude of the participating observer determines and meditates on the different possibilities and levels of experience.

The red at the zenith, one of the oldest colours, symbolizes God the Father, creative love and the divine creative fire, but also self-sacrifice and warmth.

The green in the East has from ancient times been associated with life and rebirth, the symbol of spiritual renewal. In the middle ages, green was the colour of doctors’ and pharmacists’ coats. Its quality is the expression of the resurrected Son of God, the healer and saviour.

The blue in the West stands for distance and eternity, the union with the Holy Spirit. In the history of art, blue is often the colour of Mary’s gown. “The Holy Spirit will come upon you, and the power of the highest will overshadow you” (Luke 1-35)