Normally, concrete walls require a minimum amount of maintenance. Cut out cracks to a depth of 1 inch and a width of at least ½ inch. Wet down before filling with a sand –cement mortar (two parts sand, one part cement). Repair large broken areas by cutting out sufficiently to expose reinforcing rods or mesh that will bind the new concrete to the remaining wall. Thoroughly clean and wet the cut surfaces of the wall, then coat with a slurry of neat cement and water prior to placing new material. Most defects that cause appreciable problems, such as leakage, are due to the expansion and contraction of the building members with temperature changes.
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