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Why must bricks be laid with mortar?

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Bricks are laid with mortar because it serves several essential structural and protective functions in masonry:

  • Bonding: Mortar acts as the binding agent that holds individual bricks, stones, or tiles together to form a cohesive structure.1
  • Load Distribution: Once it hardens into a stonelike mass, mortar ensures that the weight of the structure is distributed uniformly across the bonding surfaces of the units.1
  • Weatherproofing: Properly applied mortar creates a weathertight joint, which helps protect the integrity of the building from the elements.1

Additionally, the plasticity of mortar allows it to be easily applied with a trowel, enabling it to flow sufficiently to fill gaps without collapsing under the weight of the masonry units.1