A-21, r. 5.1 - Code of ethics of architects

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16. When architects formulate an opinion, give advice or prepare a plan, specifications or any other document in the practice of their profession, they must have sufficient knowledge of the facts and be reasonably certain of the proposed solution or the accuracy of the document.
Architects must not lead a client to believe that the client’s budget is sufficient for the proposed work without being reasonably certain themselves.
O.C. 901-2011, s. 16.