Reflections on the Decay Mechanisms of Half-Timbered Walls in Traditional Spanish Architecture: Statistical Analysis of Material and Structural Damage

Abstract

Knowledge on the state of conservation and vulnerability of traditional techniques when faced with the most common degradation phenomena is vital in order to propose the most suitable conservation and maintenance actions. This article presents the systematic review of 1218 half-timbered walls found throughout Spain, enabling the identification of a total of 27 material lesions, classified by atmospheric, biological or anthropic origin, and 9 structural lesions due to stress or excessive deformation. Their qualitative and quantitative analysis has focused on the frequency of the individual lesions and the possible correlation with different constructive characteristics, such as the materials used, the geometry of the framework and the presence of plinths, eaves and protective rendering. Almost the entire sample presents some degree of material degradation, mostly atmospheric lesions of limited severity, such as superficial atmospheric erosion and chromatic alteration and dehydration of the timber. In terms of structural lesions, half-timbered walls are seen to be more vulnerable to this type of deformation. Considering the risk of loss affecting all traditional architecture, it becomes particularly important to promote the continued maintenance of half-timbered walls in order to reduce the influence of material lesions caused by atmospheric agents. Subsequently, suitable criteria for intervention are established in order to reduce the effect of anthropic lesions and structural degradation phenomena, particularly linked to a lack of maintenance and modifications of anthropic origin.