Types & Causes of Cracks in Masonry Walls

Most of the types of cracks that appear in the masonry walls can be minor and insignificant in the first look, but after a certain course of time it requires expensive repair and in some cases, the only solution left is total demolition of the masonry wall. The causes of such cracks that appear in the masonry walls can be due to subsidence and settlement. Thus, it is important that one takes an immediate action to get masonry crack repair done as soon as possible to avoid further severe problems. 

Here are some of the major types and causes of Masonry cracks on the walls. 

·         Expansion cracks: The masonry walls are affected by change in the temperature and moisture level. Thus the materials experience sudden shrinkage, contraction or expansion. This results in expansion cracks. Expansive crack allow water into the cavity in brick and thus cause damage to the wall ties. If the crack is minor, then filling the crack with a mastic or sealastic compound is suggested. In case it’s major, then repair masonry crack with an expansion joint.

·         Tie failure: Wall ties are used to hold the inner as well the outer leaves of the cavity walls together. Normally, tie failure appears when the tie rusts. This causes cracks in the masonry walls. In this case, it is recommended to replace the wall ties or in extreme cases, it could result in the collapse of the wall.

·         Subsidence: The cracks caused due to subsidence is the most difficult to repair. Subsidence occurs due to reasons such as mining activity, leaking underground drainage, peak or clay subsoil or due to running sand. These cracks appear at the corner of the upper walls of the room. It requires immediate masonry crack repair and a specialist advice is required.

·         Ground heave: This is similar as the crack caused due to subsidence with a difference that the cracks would be wide at the base of the wall. This is due to the expansion of clayey soil. In the severe cases, the only solution the contractor is left with underpinning and deeper foundations. Alternate option that is available is to remove as much as possible the clayey soil from the foundation and replacing it with the hardcore is advised.