The difference between new and old brick buildings
In contrast to constructing new buildings, heritage masonry involves restoring the masonry of older existing buildings, often listed or designated for their historical significance. Construction principles for older buildings differ, requiring knowledge of heritage materials and methods to successfully restore the masonry.
Modern MAsonry construction
Modern masonry construction prioritizes hardness and impermeability, relying on cost-effectiveness. Utilizing Portland-based cements and synthetic products, the goal is to create an impervious shell around the building. While preventing water ingress is crucial, it also poses challenges when water does penetrate, as it cannot easily escape, necessitating the use of weeping holes. The rigid mortar requires expansion joints to prevent cracks from movement.
Old brick buildings
In contrast, pre-1930s buildings often feature lime-based construction, emphasizing a breathable and easily repairable structure. The softer lime-based mortar acts as a fail-safe during movement, sacrificing itself before the more expensive masonry. This characteristic facilitates easier repairs. The permeable nature of the mortar allows moisture to exit the walls, contributing to the longevity of these century-old homes.
How to restore old brick
Restoring heritage buildings mandates the use of heritage materials. Introducing hard Portland cement to a soft, molded brick building can lead to disastrous consequences. The absorbent nature of soft bricks, combined with the impermeability of Portland cement, concentrates water, making freeze-thaw cycles and salt damage a serious threat. Inexperienced tradesmen, while well-intentioned, may lack an understanding of the materials, emphasizing the importance of hiring masons experienced in heritage restoration. This decision not only benefits the aesthetics but also proves financially prudent, often involving the correction of errors from previous attempts.
To view some of our many restoration projects click here