Making decision on repointing of clay brick facades on the basis of moisture content and water absorption tests results – a review of assessment methods

Use of clay brick masonry in façades is often motivated by its aesthetic values and durability. Yet, mortar joints exposed to climate agents erode over time, expected to cause elevated moisture content and water absorption. Thus, it is often recommended that 40- to 50-year-old facades should be repointed – a measure which is intrusive and costly. Decision is in many cases taken without a clear evidence that repointing will diminish water absorption and moisture content in the renovated walls. This paper presents the results of a state-of-the-art study on field and laboratory methods to measure moisture content and water absorption in clay brick masonry. For common buildings, use of low cost and time efficient measurement methods is feasible. However, prior to measurements, analysis of technical and climate data combined with a visual inspection might give a rational basis for decision on repointing or other alternative maintenance measures.