Bricklayers leave gaps, commonly known as "mortar joints" or "joints," between bricks for several reasons:
Structural Integrity: The primary reason for leaving gaps is to provide stability and strength to the wall. Mortar joints help distribute the load and stresses evenly across the bricks, making the wall more durable and less susceptible to cracking or collapsing.
Thermal Expansion and Contraction: Bricks and mortar materials expand and contract with temperature changes. By leaving gaps between bricks, the wall can accommodate these slight movements without causing structural damage.
Moisture Management: Mortar joints play a crucial role in managing moisture within the brick wall. They allow water to escape from the wall through evaporation and drainage, preventing water from being trapped and causing damage due to freeze-thaw cycles.
Aesthetics: Properly spaced mortar joints can enhance the visual appeal of the brickwork. Different styles of joints (e.g., flush joints, recessed joints, or struck joints) can be used to create various architectural designs and patterns.
Ease of Construction: Leaving gaps between bricks makes it easier for bricklayers to lay the bricks accurately and efficiently. It allows them to adjust the position of each brick slightly to ensure a level and straight wall.
Control of Wall Thickness: Mortar joints help control the overall thickness of the wall. Bricklaying requires precision, and mortar joints provide a consistent spacing that ensures the desired wall thickness is maintained throughout.
The size of the gaps (mortar joints) can vary depending on the type of brickwork, the design requirements, and local building practices. Common mortar joint sizes range from 3/8 inch to 1/2 inch, but they can be larger or smaller as needed.
Properly proportioned and well-executed mortar joints are essential for the long-term durability and appearance of brick walls. Skillful bricklayers understand the importance of leaving appropriate gaps and take care to ensure the bricks are laid with consistent joint sizes and properly bonded to create a strong and visually pleasing brickwork structure.