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The performance of nine different vapor barrier systems comprising polyethylene (PE) membranes were assessed. The vapor barrier systems comprised membranes of virgin PE, 100% new PE, regenerated PE and multilayered virgin and regenerated PE. Membranes were joined either with tape suited to the individual system or an adhesive base on butyl rubber. The vapor barrier systems were evaluated and compared using standard laboratory tests. Chemical analytical techniques and physicomechanical tests were used. Mechanical properties were assessed using laboratory tests recommended by the harmonized standard EN 1385. Chemical analyses followed standard laboratory protocols performed with specialized equipment and visual examination. Chemical and mechanical properties were determined before and after exposure to an aging regime comprising 168 days at 70 °C in total. The chemical stability of the plastic present in each membrane was further evaluated after an additional exposure to an aging regime comprising 50 days followed by another 30 days at 70 °C. Additional aging indicated chemical changes in the membrane material with time. However, it was not possible to distinguish between aging properties for membranes containing virgin PE, 100% new PE, regenerated PE or multilayered virgin and regenerated PE. [ABSTRACT FROM AUTHOR]

• Wind-driven rain (WDR) quantification experimentally on 2 case buildings. • Effect of WDR on hygrothermal conditions in internally insulated masonry studied. • Numerical simulations to determine WDR effect on hygrothermal performance. • WDR models were found to overestimate WDR deposition. • Direct influence of WDR events on RH behind insulation was not detected. An inevitable measure when energy retrofitting historic buildings in Europe, is the reduction of building envelope heat loss. On preservation-worthy facades where external insulation is not an option, installation of internal insulation is gaining pace. The historic buildings in Denmark are often constructed with solid masonry facades and wooden decks. The internal insulation may, however, entail potential hygrothermal risks in walls and embedded wood. Measures such as vapour barriers and capillary active insulation materials are continuously evolving and the subject of much current research. The hygrothermal conditions are of great importance for the durability of the building constructions, and for the health and wellbeing of occupants. Wind-driven rain (WDR) is a central factor contributing to water penetration and moisture loads of the exterior walls. Numerous studies have shown that WDR loads influence the moisture conditions in masonry walls and embedded wooden beams, and can even affect interior relative humidity. In the present paper WDR loads on existing façades in a cold temperate climate were determined by measurements and compared to a semi-empirical model. Simultaneously, the hygrothermal conditions within internally insulated walls with exposed brick and embedded wooden beams were monitored. Furthermore, numerical simulations were implemented for clarification of WDR impact. Hygrothermal simulations and previous studies, inevitably show that high WDR loads result in higher moisture content behind the interior insulation. Results from the field measurements of WDR however, cannot directly be referred to the moisture content measured in walls behind interior insulation or beam ends. However, fluctuations in external air humidity proved to be influential on condiditons in the construction. Implementation of a semi-empirical model for calculations of WDR agreed with previous studies in predictions being too conservative when compared to measured WDR. [ABSTRACT FROM AUTHOR]