The design by Joan Alomar (Estudio Lunar) presents a building that completes the urban block and blends in to the neighborhood. In classical Roman tradition a genius loci was the protec­tive spirit of a place. This concept leads the architecture that mimics the events at it’s surroundings, the nature, vernacular architecture, etc. To blend is the rational sus­tainable concept to exist without causing a disturbance.Nowadays most of the sustainable architecture strives to produce energy regardless of the economic costs and re­sources, becoming buildings covered with items that protect them from heat, from cold and others who strive to create energy. Those buildings needed engineering to be complet­ed, to be “eco-friendly”. What if the building could protect himself? What if its own architecture was blending so well with its environment and surrounds that is not worth the effort to produce energy?

Sustainability as a complete concept is not only about sav­ing energy, the building first needs to be socially useful and improve the neighbourhood, that’s the first target of this mar­ket, is not only a market hall. The volume alienated the sur­rounding streets completes the urban block, covers a public space and creates an sculptural image to the public space.This big gesture of a cupula touching the ground in a very subtile way creates an extension of the public space where very varieties of functions could take place (market hall, per­formances, art exhibitions, meetings, dinner, etc). To create maximum flexibility the market is set up with modules, combining these modules merchants can obtain dif­ferent stalls depending on their needs. These modules can be piled up or stored in the based because its size fits in the lift.

The construction is based in “Cradel to Cradel” concepts and imitation of vernacular architecture. So the use of mate­rials from the area and local techniques will save transport and construction costs. The main volume will be build like the old cisterns, using a material based on neighbour recy­cled demolition materials reinforced with steel. The shape, structurally efficient will save material, protect from direct sun and provide thermal mass. Add the same time this majestic shape gives notoriety as a public market. One of the main points of this building is its cistern at top level, not only for its sustainable contribution but for its ex­trapotential addition to the building functions, it will act as attractor point for all Casablanca citizens, creating new commercial opportunities in the neighbourhood.

The water accumulated in the building provides isolation to the building and creates new areas for flora and fauna. This water provides from direct rain collection and neighbours roofs, will be used in toilets and market hall for cleaning por­puses, due to the level difference it won’t need any energy to be pumped. In conclusion the building results of the mix of traditional market interpretation, vernacular architecture and sustain­ability as result of using what nature and rationality offers.