Many museum buildings have incorporated systems that allow daylight to illuminate their galleries, but none as robustly as MAXXI, where almost every roof surface is glazed. To support such a roof above the museum’s winding galleries, whose bays average 40 feet wide, reinforced-concrete walls on either side sandwich a series of trusses. While these trusses run parallel to the gallery walls, transversal steel beams connect the walls. Originally conceived as a precast-concrete element, each of these longitudinal sections, typically six per bay, is composed of a steel truss encased in 1⁄2-inch-thick fiberglass-reinforced concrete panels. The nearly 8-foot-deep assembly, which rises 20 feet above the floor, supports an exterior metal solar-shading grille that doubles as a maintenance walkway above the double-glazed units of the glass roof. Below the glazing, aluminum louvers automatically adjust to control the amount of light that enters a gallery based on lux levels measured by a building management system.

Roller blinds are used to block out light entirely when required. The channels at the bottom of alternating fins contain either spotlights (to augment fluorescent lighting housed above the louvers) or tracks for suspending speaker boxes, projectors, or similar items for installations and performances.