Masonry walls are used in constructing buildings, boundaries, and many other structures on site. This constitutes blocking materials to erect walls. In the course of construction or after cracks may appear on the walls. This has to be corrected in order to have a stable structure. This can be caused by the use of different materials with varying strengths. The other reason may be due to differential settlement of the building structure in the foundations.
When repairing cracks on a masonry wall, the type of structure must be taken into consideration. This is because the wall may be non-load-bearing or load-bearing. For the load-bearing ones, it’s critical to access the level of cracking. The structure is checked from the floor level to the roof ring beam. This will ensure that all stones on the fault line are identified. In non the load-bearing, assessment is done and correction is done superficially.
The repair of cracks in masonry walls commences by raking out the mortar or plaster. This is done to a depth of two inches. All vertical and horizontal joints are exposed along the faultline. Hoop Iron is then cut and laid course wise. The strip is placed at the deepest end of the joint. It is placed on top of the crack one block length on both sides. For severe damage, each course is raked out. A steel bar is used of a minimum of ten millimeters diameter.
When the crack in masonry is being repaired, rich concrete is added to the joint. After the concrete slurry fills the joint, it is allowed to dry for one day. The wall is then plastered again.the plaster mix should not exceed one part cement and two parts sand. This is to balance the material strengths to avoid cracking again on plaster. After the plaster is completed, it is allowed to dry. It should be cured for two weeks before any decorations.