# Atlas of Defects within a Global Building Inspection System
## 4 Discussion  
Considering the excerpts of the atlas of defects presented in Figures 3 and 4, cases of defects \"A-A3 Dirt and accumulation of debris\" and \"A-C2 Oriented cracking on the current surface\" may be analysed and classified in terms of urgency of repair. Figure 5 shows three different window frames affected by \"Dirt and accumulation of debris\" (A-A3). The window frames in Figure 5a,b are of anodised aluminium and the one in Figure 5c of reinforced concrete. To determine the urgency of repair of each window frame, the criteria determined in the atlas of defects should be analysed, starting at the most urgent level of repair, which is level 2, for door and window frames (Figure 3). In Figure 5, none of the observed debris has high chemical aggressiveness. In terms of aesthetical value, the window in Figure 5b is located on a front facade, thus having high aesthetical value. The observance of this criterion alone makes this a case of level 2 of urgency of repair, even though only a white spot of paint is observed in the window frame. As for the incorrect operation of moveable leaves, Figure 5b,c show fixed windows, but Figure 5a shows a sliding window, where the accumulation of debris next to the sliding guides probably hinders the movement of the leaves and prevents them from shutting completely. So, the case in Figure 5a is also of level 2 of urgency of repair. This case also shows obstruction of the drainage holes of the window frame, which reinforces the need for intervention in the short-term (level 2). The case in Figure 5c does not match any of the criteria stated for level 2 and thus is considered a situation with level 3 of urgency of repair. It is interesting to conclude that both cases in Figure 5a,b have the same level of urgency of repair while being so different, with the debris of Figure 5a appearing to be much more worrying. If considered in the classification parameters, the aesthetical value of the affected areas may be very influential. Accumulation of debris is also a factor considered by [PERSON] et al. [64] to determine the degradation level of window frames. The accumulation of debris is considered to have a low impact on the overall degradation condition of window frames, thus being associated with a weighting coefficient of 0.1. Furthermore, whether this defect affects sealings, fittings or framework materials and coatings, it is always rated as level 1 of defect condition (from 0 to 4, from the least to the most severe), even if the accumulation of debris affects more than 20% of the component. An assessment of the defect's effects is taken into account, considering that corrective cleaning operations can eliminate this defect and regular cleaning may prevent its reoccurrence. Still, [PERSON] et al. 's [64] approach does not invalidate the urgency of repair approach, as the low impact of a defect's effects in terms of degradation does not contradict the importance of eliminating such defect, even more so when the defect may cause other damages in the future. Figure 6 presents six cases (a-f) of \"A-A3 Dirt and accumulation of debris\" on wall renders. Two cases per building are shown: Figure 6a,b occur in the same building, Figure 6d,e occur in another building and Figure 6c,d occur in yet another building. For wall renders, defect A-A3 is classified from levels 1 to 3 of repair urgency (Figure 3). As for window frames, to assign a level of urgency of repair to each case in Figure 6, they must be analysed in light of the criteria determined for each level, starting from the most urgent one. So, if the affected areas are of high aesthetical value, level 1 applies, which is the case in Figure 6a,f. Then, situations with an affected area larger than 65% of the surface and high probability of repetition of the phenomenon are also considered as level 1 of urgency of repair. Figure 6d observes these criteria, with about 77% of the surface affected by the accumulation of dirt associated with a thermophoresis phenomenon and no measures implemented to stop the defect from progressing.