This paper describes a methodology for assessing damage threshold criteria. The methodology includes a survey and determination of threshold values for deterioration, which can then be used to evaluate the risk in specific structures of external walls. The work includes summarizing existing knowledge and adapting and developing models for failure modes based on field and laboratory testing. Failure modes include frost damage of the exterior façade layer, rot and mould growth within the building envelope and adjoining structures, as well as discolouring of façade surfaces due to biological growth.

Click http://eehb2018.com/wp-content/uploads/2018/09/Conference-Report-The-3rd-International-Conference-on-Energy-Efficiency-in-Historic-Buildings.pdf">here for the full version, p. 34.