Fig. 5

Comparison of all mortar joints and granite units over time, based on their moisture level value at surface (a) and depth (c) and on the differences of moisture level (MI) since “before-rain” measurement at surface (b) and depth of the wall (d). Dashed lines and blank points represent the effect of high RH due to a rain event outside the sheltered area. The two blue lines for wall 1 represent the two runs of testing. x-axis represents different time intervals. t0 h = rain simulation and MI 0 (b and d) = MI value at start of the experiment. Data from surface and depth cannot be directly compared