Cracks in a wall can develop from different mechanisms when components exceed their strength capacity. Some cracks are minor and non-structural, but others could be a harbinger of major structural problems. Walls present significant issues from the perspective of sustainability, which call for a basic comprehension of crack behaviour. Through site inspections and physical surveys of two-story terrace buildings in Seri Iskandar, Perak Darul Ridzuan, this study attempts to apply a qualitative approach to understand the reasons for wall cracking. Cracks were assessed based on width, orientation (vertical, horizontal, and diagonal), using crack comparator guidelines from Jabatan Kerja Raya (JKR), Malaysia. Crack widths were classified as wide and medium based on content analysis. The factors that have been identified include heat expansion and contraction, inadequate brickwork, overloading, shrinkage, structural deterioration, soil behavior (such as uneven soil pressure, weak soil, settlement, and movement), and external pressures. As cracks impact the serviceability and long-term sustainability of the wall, more cooperation and collaboration need to be accomplished by the parties involved (i.e., contractors, consultants, manufacturers, and suppliers) to minimize the cracking and enhance wall performance in sustainable construction in the future.