Inefficient perforated zinc panels on school in Barcelona 
The considered building is the extension of Sant Gregori School in Barcelona, to be used as a small music school.
In this building, the solar shading is achieved through exterior zinc perforated-sheet shutters (same as the outer sheet of the façade, but homogeneously perforated). These small perforations allow outward visibility, but not inward, while partially protecting from solar direct radiation.
But as we can see in the last picture, the density of the perforations is too high as the sun can freely enter even with closed shutters. This could be attenuated with a lower proportion of perforation-opaque, which would also bring lower vision through them; or a deployé, whose shape would block better the sun, and open to the outside views.
Andrea Gago Alonso, ETSAB student 2013
Ph1: from Acieroid
First drawing: Andrea Gago Alonso, ETSAB student 2013