3.2.2. Computer Classroom

As discussed in Section 3.1, the computer classroom differs from the standard classroom only in terms of the furnishing layout, so theoretically it would be possible to apply the same measures that are discussed above. However, the discontinuous use of this room suggests to implement different and more flexible solutions, with lower impact on room geometry and possibly on construction costs as well.

Accordingly, the focus was on reducing the high illuminance values in proximity of the windows, where approximately one-third of the desks are accommodated. To this aim, the benefits of using reflective glazing with visible transmittance as high as 0.5 and internal blinds (curtains) with diffuse reflectance equal to 0.45 have been analysed as two different options (see Figure 7).

**Figure 7.** Design solutions for the computer room.

Both of the alternatives behave rather similarly, but a preference is given to the installation of curtains because of the costs and the higher flexibility of use over reflective windows.

By comparing the metrics for the existing and the refurbished cases (Table 6), it can be observed that the main contribution of the curtains is the reduction of the amount of light entering the room, as demonstrated by the lower *sDA* (81.6% against 96.5%) and *UDI* exceeded values (3.6% against 23.4%). Nonetheless, the reduced incoming light brings some benefits in terms of useful *UDI*, since now the average illuminance value is expected to be in the range of 100 lux to 2000 lux for 96.1% of the time against the original 76.3% value. The *UR* also improves, increasing from 24% to 33%, but it still keeps below the threshold of 60% prescribed by the Italian regulations.


**Table 6.** Daylight metrics for the computer classroom: existing and refurbished scenario.

Negligible differences are expected in terms of *aDF* (2.4% of the refurbished case against 2.6% of the base case), while it is worth noticing how the *ASE* value keeps constant at 49%, just because this is calculated without accounting for the operation of movable shading devices, according to the IES definition [4].

Finally, the annual *DGPs* calculation reported in Figure 8 shows no glare occurrence at every time of the year. This happens because curtains are supposed to be used whenever the *DGPs* calculation for the observer's viewpoint is expected to be above 0.40; different activation strategies would likely perform differently, but they have not been further explored because of the discontinuous use of this room.

**Figure 8.** Annual *DGPs* calculation for the computer classroom. Refurbished scenario.
