Why Do Bricks and Mortar Crack and How Can I Repair Them?

Bricks and mortar get damaged for many reasons. A common cause of cracks is water penetration or moisture induced damage. Mortar is comprised of sand, cement, and lime. This mixture is ideal for use in narrow and vertical applications such as between stone or bricks; however mortar is more susceptible to water erosion than cement or other materials. Bricks and mortar crack as water penetrates eroded areas and damage will continue to spread if it is not repaired. A common example of water damage occurs on limestone window sill joints. Water infiltrates cracks or poorly sealed areas near the window and trickles down to erode and damage mortar joints around the limestone sill.

Mortar joints may also crack or deteriorate due to excessive vibration. Buildings and structures located near train tracks, large roadways, or high traffic areas tend to have more cracks in their bricks and mortar due to higher amounts of vibration. Bricks and mortar are inflexible materials so constant vibrations will eventually create stress, damage, and cracks.

Foundational and structural issues such as load-bearing tolerances will also affect how and when mortar joints crack. A foundation that is still settling will create distinct step cracks that run along brick and mortar joints. An overly loaded brick wall will exhibit buckling or bowing.

Finally, factors such as when or where the home or building was built, what materials were used, and what type of maintenance is performed can also affect the integrity, appearance, and condition of bricks and mortar joints.

It’s a good idea to visually inspect your building, home, or brickwork every 3-6 months to assess if any areas need attention before serious problems develop. If you notice damage along your bricks or mortar a masonry professional should examine the issue. In most cases a tuckpointing or brick repair project will fix the damage and restore the affected area. Proper maintenance prevents cracks from spreading and helps ensure the long-term aesthetic and structural integrity of your brickwork.