A Housing or Construction Defect is a building flaw or design mistake that reduces the value of the home, and/or causes a dangerous condition. Some defects are obvious (such as water seepage) but many are less obvious and do not become apparent until years after a building was constructed. A construction defect can arise from a variety of factors, such as poor workmanship or the use of inferior materials. Common examples of housing and construction defects are water leakage, faulty electrical or heating systems in a home, indoor mold growth, dry rot, and unstable landscaping.