*3.1. Existing Scenario*

### 3.1.1. Standard Classroom and Computer Classroom

The standard and computer classrooms behave differently from the gym, but in a similar way to each other because of the same orientation and of the identical geometric layout and finishing materials. Only slight differences are recorded, imputable to the different furniture only, thus the results of both rooms are presented together for the sake of brevity.

As shown in Table 4, where the calculation of each metrics is reported for the existing configuration, in none of these spaces the statutory *aDF* and *UR* thresholds (amounting to 3% and 60%, respectively) are satisfied. In fact, the *aDF* values amount to 1.8% in the standard classroom and to 2.6% in the computer room, while the UR values are 37% and 24%, respectively.


**Table 4.** Daylight metrics for the existing scenario.

The *sDA* metrics suggests a good daylight availability in both cases, with around 90% and 96% of the room area that is daylit with more than 300 lux for at least half of the occupancy time. *ASE* values of 53.4% and 49% are predicted in the standard classroom and computer room in order, which are significantly lower than the 68.2% value that was recorded in the case of the gym (see next subsection) because of the lower amount of glazed surfaces and of the different orientation, which excludes the direct sunlight contribution for most of the time.

In terms of *UDI* distribution, the percent of time when daylight levels fall within the useful range is pretty much the same for these rooms, being around 72% for the classroom against 76% for the computer room, while the percent of occupied time within the *UDI* > 2000 lux bin is around 23% in both cases.

If looking at glare issues, the fisheye pictures that are reported in the Appendix A refer to the observers' point of view reported in the plans. The glare sources are highlighted as coloured patches, together with the instantaneous *DGPs* values achieved during a summer day (1 June at 10 a.m.) and a winter day (1 December at 10 a.m.). The observers' positions have been chosen by running the simulations under clear-sky conditions and identifying the points where the illuminance values were the highest at solstices and equinoxes. In the case of the standard and computer classrooms, very different instantaneous values of *DGPs* both in wintertime (0.48 for the standard classroom against 0.16 for the computer classroom) and in summertime (0.62 against 0.19, respectively) are predicted.

This different behavior is confirmed by the annual *DGPs* calculations for the same observers' position, as reported in Figure 4a,b through the "month-hour" diagrams, which was first introduced by Kambezidis et al. [26]. Here, the columns identify the month of the year, and the rows identify the hours of the day. The hourly *DGPs* values are reported using coloured patches: green patches stand for

imperceptible glare (*DGPs* < 0.35), yellow patches for perceptible glare (0.35 ≤ *DGPs* < 0.40), orange patches for disturbing glare (0.40 ≤ *DGPs* < 0.45), and red patches for intolerable glare (*DGPs* ≥ 0.45).

**Figure 4.** Annual Daylight Glare Probability (*DGPs*) calculation for the current configuration: (**a**) standard classroom; (**b**) computer classroom; and, (**c**) gym.

What emerges from these pictures is that intolerable glare is seldom predicted for the classroom, and this happens only for some hours during winter and transition seasons (January to April and September to December) from 10 a.m. to 11 a.m., when the sun's position is lower over the sky. On the other hand, intolerable glare is expected for the computer classroom for most of the occupancy time throughout the year, mainly because the selected observer is close to the window and it suffers from reflections of direct sunlight on the monitors.
