The lattice is real concrete lacework comprising 400 panels measuring 6 x 3 m each. It is braced horizontally using double-articulated struts that punctuate the walkway along the peripheral walkway. That fibre-reinforced lace concrete plays no structural role. It serves as a filter, protecting the interior cube of the Mucem and the peripheral promenade from the sun and wind. Its pattern may be reminiscent of a variety of references like mashrabiyas or coral.

Ultra-high performance fibre-reinforced concrete (UHPFRC) is the fruit of French research. For the past 20 years, it has been used to create chemical tanks and works of art. As suggested by its name, that concrete contains metal and/or synthetic fibres that produce excellent results in terms of traction (stretching). Concrete chemists studied the granular stack to ensure the spaces were as small as possible, so that the concrete would become very dense. Its composition endows it with three key qualities: resistance to compression that is six to eight times higher than that of classic concrete, perfect tightness thanks to its very low porousness, and an ability to follow the most varied of moulds. The Mucem’s architecture was made possible by the properties of this material.