Mortar Damage on Brick Walkways

Causes of Damage

• Exposed to the wear and tear of foot traffic and natural elements, the causes of damage vary depending on your region and the quality of installation, among other factors. If the walkway is not sealed, the sun can dry out mortar joints, making it brittle and vulnerable to chipping. If the foundation beneath the walkway is not deep or compact enough, frost heave damage, caused by the ground freezing and expanding, can dislodge a section of bricks and crack the mortar.

Preventing Damage

• One of the best ways to prevent damage to a brick and mortar walkway is to dig out the site lower than the frost line. A thick gravel base helps absorb tension when the ground freezes and provides strong, long-lasting support. Pitch the width of the gravel base on a slight slope toward the lower-lying side of the walkway to direct water from the surface, preventing moisture from forming puddles and permeating mortar. Once the walkway is laid, roll penetrating exterior sealant over the surface to repel water and strengthen the mortar.

Repairs

• Before patching missing chunks of mortar, you must first clean out debris from the damaged area. Use a wire brush and hose to force out dirt, sticks and broken pieces of mortar that will otherwise weaken the patch. Once the surface is dry, use a putty knife and tamp wet mortar into and holes or cracks. Smooth the surface with a concave joint tool or a gloved finger and wait for it to dry before using the walkway.

Considerations

• Damaged mortar can lead to larger problems if left unrepaired. Once enough mortar chips away, the bricks are vulnerable to chipping or dislodging from the walkway. Debris will build up inside gaps, creating an eyesore and maintenance challenge if weeds begin to grow. Moisture can also permeate the gaps, loosening the gravel foundation beneath and causing the surface to sink.