Without question, a contractor who performs substandard work and delivers a defective product will be held responsible for correcting the defect, and probably for any damages caused by it. Contractors have a duty to perform their work in a workmanlike manner and with ordinary and reasonable skill. The law measures a contractor's performance against that of an imaginary reasonably prudent contractor, who practices the profession with the degree of care and skill customarily found in the trade. This seems fair enough. It also seems fair that a contractor who knowingly purchases and installs defective materials will be found liable for the costs caused by the defect. But should contractors be held responsible for a defect if they had no reason to suspect
