Investigation of Brick Masonry Wall Crack Patterns in Residential Buildings in Enugu State

Wall cracking in brick masonry residential buildings is a prevalent construction defect in Enugu State, South East Nigeria, and a systematic investigation of crack patterns, causes, and severity distribution provides the technical basis for improved construction practice and repair guidance. This study investigates crack patterns, types, and probable causes in 60 residential buildings in Enugu metropolis through visual inspection and occupant interviews. Buildings were selected from three age categories: less than 5 years, 5 to 15 years, and above 15 years. Crack mapping was conducted on all surveyed buildings using a structured crack documentation form, classifying cracks by pattern, width, location, and probable cause according to the Building Research Establishment classification methodology. Results indicate that diagonal cracking at openings is the most prevalent type, occurring in 67 percent of buildings. Settlement-related cracking is most common in buildings below 5 years of age, attributed to inadequate sub-grade preparation and sub-standard foundation depth. Thermal and moisture-movement cracking is predominant in older buildings. Crack widths exceeding 5 mm (structural concern) are found in 23 percent of assessed buildings. Most cracks (61 percent) are associated with buildings constructed without engineering supervision. The study concludes that poor foundation design and inadequate sub-grade assessment are the primary causes of cracking in Enugu residential buildings, recommending site investigation as mandatory before construction.

Keywords: masonry cracking, crack patterns, residential buildings, foundation defects, Enugu State