Assessing Efficiency of Protective Treatment Materials for Brick Structures

Protecting the existing brick masonry structures efficiently is a part of sustainable development in the built environment. The effective choice of compatible products in such restoration process as described in this paper reduces the chances of future frequent interventions due to earlier improper repair. In this study, two types of most commonly adopted water-repellant coatings were evaluated for their essential properties like hydrophobicity, breathability, penetration depth and salt weathering resistance in bricks of different inherent properties. Two types of bricks with different pore structure were treated with an acrylic and a silicone-based water-repellents. The breathability and water-absorption of the coatings were measured. Silicone-based treatment was found better with the fundamental requirements—being more water-impervious. However, on studying the performance in accelerated salt crystallization tests, it was found that silicone-based coatings had an adverse effect in the performance of the system, whereas acrylic coatings could improve the salt-resistance. The paper outlines a methodology to be adopted on choosing a protective treatment for a brick structure from the experimental results for obtaining the maximum performance. The methodology follows standard tests for measuring water-repellency, succeeded by the evaluation of breathability and salt weathering resistance of the coating.