# Operationalisation of Building Inspections and Repair: Systematisation-Based Approach
## 3 Results
### Most Common Types of Repair Techniques
#### 3.2.1 Repair Techniques in Roof Claddings  
In Table 14, the most relevant inter-defects correlations in roofs are presented, namely, different relationships between defects \"A-A1 Leakage damp\", \"A-A3 Dirt and accumulation of debris\", \"A-B1 Biodeterioration/biological growth\", \"A-B2 Vegetation growth\", \"A-C1 Mapped cracking\", \"A-C2 Oriented cracking on the current surface\", \"A-C3 Fracture or splintering on the current surface\", \"A-D7 Absence/loss of filling material in connecting elements or current joints\", and \"A-D9 Insufficient or excessive overlap of the claddings elements in roofs\". According to the data of [PERSON] et al. [40], adapted to the harmonisation of the classification of defects [33], defects **A-B1 and A-B2**, together, are the most common in **external claddings of pitched roofs** (in 72.5% of inspected roofs). Then, defects A-C1, A-C2, and A-C3, all together, also have a high incidence (46.4%). Defect A-A3 (28.0%), as highlighted in Section 3.1, moderately affects claddings of pitched roofs, and defects A-D7 (6.8%) and A-D9 (12.6%) only affect a few pitched roofs. As for **flat roofs**, according to the data of [PERSON] et al. [41], adapted to the harmonisation of the classification of defects [33], as mentioned in Section 3.1, defect \"**A-A3** Dirt and accumulation of debris\" is the most detected (in 74.3% of inspected flat roofs). Defects A-C1, A-C2, and A-D7, all together, have a median incidence in flat roofs (21.9%). Then, defects A-D9 (13.3%), A-C3 (11.0%), and A-A1 (9.5%) only affect a small number of inspected roofs. As for the severity of the set of defects included in the most relevant correlations in roof claddings, data from service life prediction methodologies may be considered. In the case of external claddings of pitched roofs, the severity implicitly associated with the degradation levels for defects by [PERSON] et al. [42] may be used. Out of the nine mentioned defects, these authors only take into account \"A-A3 Dirt and accumulation of debris\", \"A-B1 Biodeterioration/biological growth\", \"A-B2 Vegetation growth\", \"A-C1 Mapped cracking\", \"A-C2 Oriented cracking on the current surface\", and \"A-C3 Fracture or splintering on the current surface\", which comprise the defects \"Staining, change in colour or of brightness of the tiles\", \"Development of parasitic vegetation/biological colonisation\", and \"Cracking/fracture\". The first one was already considered in Section 3.1.1, and it is considered to affect moderately degraded roof claddings. Biological colonisation and vegetation growth, together, are admitted to affect up to 10% of the total area of the cladding when it is in good condition (Level 1). On the other hand, if they affect more than 50% of the pitched roof cladding, then it should be considered moderately degraded (Level 3). Cracking/fracture was also considered in Section 3.1.1, and it affects roofs from slight degradation (Level 2) to generalised degradation (Level 4). [PERSON] et al. [42] use a five-level scale from Level 0 (Very good) to Level 4 (Generalised degradation). From this data, defects A-C1, A-C2, and A-C3 are the most severe. As for flat roofs, the same kind of analysis cannot be performed. Still, as mentioned in Section 3.1.1, the importance of \"A-A1 Leakage damp\" is highlighted in the literature [43].