## 3 Results and Discussion
### Assemblies Hygrothermal Assessment: Current Climates
#### 3.2.1 Water Content within Assemblies  
In temperate climates, the application of a render causes a significant decrease in water content during the wetting phase and slightly higher values for the drying phase (Figure 8a,b). The decrease in water content during the wetting phase, i.e., when the wall is \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline
**Climate** & **Jan** & **Feb** & **Mar** & **Apr** & **May** & **Jun** & **Jul** & **Aug** & **Sep** & **Oct** & **Nov** & **Dec** \\ \hline Zurich & & & & & & & & & & & & \\ \hline Essen & & & & & & & & & & & & \\ \hline S. Francisco & & & & & & & & & & & & \\ \hline Lisbon & & & & & & & & & & & & \\ \hline \end{tabular}
\end{table} 
Table 3: Wetting and drying cycle for the studied climates. Each month is divided into three points: beginning, middle, and end. The wetting phase is identified in blue and the drying phase in red. Figure 7: Normals of the maximum (**a**) and minimum (**b**) outdoor temperatures for two periods: 1951–1980 (used in Ref. [56]) and 1970–2000 [57]. subjected to a great amount of moisture from the exterior ambience, is due to the fact that the renders' moisture transport properties are lower than those of the solid brick; hence, the layer of solid brick has a lower amount of moisture. During the drying phase, i.e., when the boundary conditions compel the wall to expel moisture, the application of a render layer causes higher water contents since it reduces the evaporative capacity of the solid brick. On the other hand, the application of plaster results in an increase in water content for temperate climates, which is more obvious during the wall's drying phase (Figure 8c,d). All unrendered simulated walls have the same layer in direct contact with the exterior ambience (i.e., solid brick). Thus, the amount of moisture that penetrates into the solid brick is similar. However, due to the mortars' moisture transport properties, it is harder for moisture to reach the interior ambience. Consequently, moisture is stored at the interface between the solid brick and the plaster. This moisture storage could have been influenced by the moisture transport resistance, which is generated by the interface characteristics between layers. However, this type of resistance is not considered in WUFI. These two behaviours are more significant, depending on how impermeable the mortar is to moisture. A wall coated on both surfaces has a similar behaviour to that of a rendered wall, but with slightly higher values of water content since the plaster reduces the evaporative capacity of the solid brick. In cold climates, plasters also cause an increase in the solid brick's water contents directly proportional to the moisture transport properties of mortars. However, the application of a render layer in this type of climate does not have all the same implications as the ones previously described for temperate climates. Although the application of a render  
Figure 8: Water content of the solid brick for the standard case (SC) and rendered cases in S. Francisco, SF (**a**), and Lisbon, LX (**b**) where LR is lime, LCR is lime-cement, and CR is cement renders; and water content of the solid brick layer for the standard case (SC) and plastered cases in S. Francisco, SF (**c**), and Lisbon, LX (**d**), where LP is lime, LCP is lime-cement, and CP is cement plasters. layer also causes a decrease in water content during the wetting phase and higher water content values during the drying phase, the case with the highest water contents changes throughout the year (Figure 9). During the wetting phase, the standard case absorbs more moisture than the other cases due to its higher moisture transport properties (see Figure 3). During the drying phase, the standard case expels moisture easier than the rendered cases, since it does not have the render layer decreasing the evaporative capacity. The lime-cement rendered case is, for most of the year, the one with the highest water contents.