3.2.3. Gym

In the case of the gym, the main issue to be tackled is the rather high illuminance values due to direct sunlight only, as expressed by an *ASE* = 68.2%. When considering that this room presents large glazed surfaces exposed both due to east and west, which are hit from direct sunlight during the morning and the afternoon, respectively, when the sun height is low on the horizontal, the proposed intervention aimed at excluding this contribution by applying louvers on both sides.

The optimal configuration, achieved by running several simulations, was found when using aluminium blades of 0.25 m width, separated from each other by 0.25 m, and showing a diffuse reflectance that is equal to 0.5 and a specular component equal to 0.2.

Moreover, a double-curved false ceiling is proposed, hanging down by approximately 1 m from the centreline of the roof and showing the same optical properties as the false ceiling being applied to the standard classroom (0.85 diffuse reflectance and 0.2 specular reflectance). This is expected to raise the *UR* from the original 68% value (see Figure 9 for an axonometric representation of the proposed interventions).

Simulation results show that, despite that the gym is almost entirely lit with more than 300 lux for at least 50% of its occupancy time (*sDA* = 99.2%), the ASE value is now as low as 12.1% and the time during which illuminance is higher than 2000 lux is only 5.7% of the occupancy period against the original 6.4% value. Moreover, even if the *aDF* drops down from 3.4% to 1.8%, the useful *UDI* metrics

has slightly improved (from 93.6% to 94.3%), meaning that indoor lighting conditions are improved rather than worsened (Table 7).

**Figure 9.** Design solutions for the gym.


**Table 7.** Daylight metrics for the gym: existing and refurbished scenario.

Finally, the annual *DGPs* calculation reported in Figure 10 for the observer's position depicted in the Appendix A clearly indicates that with the proposed interventions intolerable glare is expected only for very few hours in a year (around 11AM in February and September and around 5PM in April and September). In the remaining of the year, glare conditions are tagged as imperceptible (i.e., with *DGPs* < 0.35); this represents a strong improvement if compared with the annual *DGPs* calculation of the existing case reported in Figure 4c.

**Figure 10.** Annual *DGPs* calculation for the gym. Refurbished scenario.
