Impact of Water-Repellent Products on the Moisture Transport Properties and Mould Susceptibility of External Thermal Insulation Composite Systems
Source abstract
Abstract
External Thermal Insulation Composite Systems (ETICS) are constructive solutions widely used to increase the thermal insulation in new and retrofitted buildings. However, these systems can present several anomalies due to their constant exposure to weathering agents and anthropic factors. Water is generally the major cause of degradation. Thus, the application of water-repellent products can minimize the appearance of anomalies and increase the durability of the systems. In this paper, acrylic-based and siloxane-based hydrophobic products were applied to ETICS, with the aim of assessing the compatibility, effectiveness, and durability of these products. The moisture transport properties and mould susceptibility were assessed through laboratory tests on untreated and treated specimens. The durability of the hydrophobic treatments was also evaluated through artificial aging tests (heat-cold and freeze-thaw cycles). Results show that the protection products generally decreased water absorption, slightly decreased the drying rate, and presented adequate water vapor permeability. After aging, the products still had reasonable effectiveness and, with one exception, improved the water vapor diffusion of the systems. Additionally, ETICS underwent an alteration in the finishing coat (possible modification of the porosity) due to the aging cycles. No clear linear correlation was found between the contact angle values and water absorption results, evidencing the influence of other factors related to the composition of the water-repellent products.
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Research context
OpenAlex topics: Building materials and conservation · Hygrothermal properties of building materials · Facilities and Workplace Management
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
CERIS, Civil Engineering Research and Innovation for Sustainability, Instituto Superior Técnico, University of Lisbon, 1049-001 Lisbon, Portugal
Buildings Department, LNEC, National Laboratory for Civil Engineering, 1700-066 Lisbon, Portugal
Structures Department, LNEC, National Laboratory for Civil Engineering, 1700-066 Lisbon, Portugal
cE3c, Centre for Ecology, Evolution and Environmental Changes, Azorean Biodiversity Group, University of Azores, 9700-042 Azores, Portugal
Funding
Portuguese Foundation for Science and Technology
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