In this paper different configurations of an open-space office located in Rome has been simulated with EnergyPlus 8 to compare the performance of outdoor and indoor shading devices concerning the thermal and visual comfort and the overall primary energy use. The standard PMV indices [1] have been calculated considering also the effect of the diffuse and beam solar radiation directly reaching the occupants through the windows. Although the use of shades always improves the thermal comfort, the energy demand could increase as an effect of the internal position of shades in combination with particular orientations and glazing types