A modular shielding apparatus for building facades, comprising: - at least one barrier movable between an open position and a closed position; - a support structure for said at least one barrier, adapted to be fixed to a building facade, the support structure being adapted to position the barrier at a minimum distance from the building facade of between 40 cm and 80 cm; - at least one sliding guide (20; 22) for said barrier; and - movement means adapted to move said barrier along a sliding direction (x) on said at least one sliding guide (20; 22) between said open position and said closed position; wherein said at least one barrier comprises a first barrier element and a second barrier element being adjacent to each other in the closed position of the barrier, each barrier element (26, 28) comprising a first panel (262; 282) and a second panel (264; 284); wherein said first panel (262, 282) and said second panel (264, 284) are micro-perforated; said first and second panels (262, 264; 282, 284) of each respective barrier element (26, 28) being connected to each other at adjacent edges by hinge means (30; 32) defining a hinge axis (302, 322), said first and second panels (262, 264; 282, 284) of each respective barrier element (26, 28) being adapted to rotate relative to each other about said hinge axis (302, 322); said first panel (262, 282) being rotatably connected to the support structure, and said second panel (264; 284) being provided with sliding means (268, 288) adapted to slide with respect to said at least one sliding guide (20; 22), and adapted to allow a relative rotation between said at least one sliding guide (20, 22) and said second panel (264, 284); wherein said first panel of the first barrier element is rotatably connected to an upper portion of the support structure, and said first panel of the second barrier element is rotatably connected to a lower portion of the support structure; in said closed position of said barrier, said first and second panels (262, 264; 282, 284) having lying planes inclined with respect to one another and to the direction defined by said sliding guide (20; 22), protruding in the opposite direction with respect to said building facade. - at least one barrier movable between an open position and a closed position; - a support structure for said at least one barrier, adapted to be fixed to a building facade, the support structure being adapted to position the barrier at a minimum distance from the building facade of between 40 cm and 80 cm; - at least one sliding guide (20; 22) for said barrier; and - movement means adapted to move said barrier along a sliding direction (x) on said at least one sliding guide (20; 22) between said open position and said closed position; said at least one barrier comprises a first barrier element and a second barrier element being adjacent to each other in the closed position of the barrier, each barrier element (26, 28) comprising a first panel (262; 282) and a second panel (264; 284); wherein said first panel (262, 282) and said second panel (264, 284) are micro-perforated; said first and second panels (262, 264; 282, 284) of each respective barrier element (26, 28) being connected to each other at adjacent edges by hinge means (30; 32) defining a hinge axis (302, 322), said first and second panels (262, 264; 282, 284) of each respective barrier element (26, 28) being adapted to rotate relative to each other about said hinge axis (302, 322); said first panel (262, 282) being rotatably connected to the support structure, and said second panel (264; 284) being provided with sliding means (268, 288) adapted to slide with respect to said at least one sliding guide (20; 22), and adapted to allow a relative rotation between said at least one sliding guide (20, 22) and said second panel (264, 284); wherein said first panel of the first barrier element is rotatably connected to an upper portion of the support structure, and said first panel of the second barrier element is rotatably connected to a lower portion of the support structure; in said closed position of said barrier, said first and second panels (262, 264; 282, 284) having lying planes inclined with respect to one another and to the direction defined by said sliding guide (20; 22), protruding in the opposite direction with respect to said building facade.