Home inspections began as a consumer service in the 1970's in direct response to the growing demands by home buyers. It soon became apparent that selecting a home inspector was becoming as important as finding the right home. To meet this need, the Canadian Association Home and Property Inspectors (CAHPI) was formed in 1982, followed by the Ontario Association of Home Inspectors (OAHI) in 1987. OAHI operated as a chapter of the American Society of Home Inspectors (ASHI), until 1994 when the OAHI became a self regulating professional body with the passage of the Ontario Association of Home Inspectors Act.

The Ontario Association of Home Inspectors Act received royal assent on December 9, 1994, enabling the OAHI to define qualification and performance requirements and the exclusive right to grant the designations "Registered Home Inspector" and "RHI" to qualified members in the Province of Ontario. OAHI is the leading edge of the North American profession as the first self-regulating home inspection organization, with associations in other jurisdictions following the OAHI's lead.

The Ontario Association of Home Inspectors is dedicated to enhancing the technical skills and professional practice of home inspectors, and maintaining high professional standards through education and discipline. The OAHI Standards of Practice provides inspection guidelines, and the OAHI Code of Conduct defines the member's responsibility to act in a strictly fair, impartial, and professional manner.