Iowa Code § 17A.16

(1) A proposed or final decision or order in a contested case shall be in writing or stated in the record. A proposed or final decision shall include findings of fact and conclusions of law, separately stated. Findings of fact, if set forth in statutory language, shall be accompanied by a concise and explicit statement of underlying facts supporting the findings. The decision shall include an explanation of why the relevant evidence in the record supports each material finding of fact. If, in accordance with agency rules, a party submitted proposed findings of fact, the decision shall include a ruling upon each proposed finding. Each conclusion of law shall be supported by cited authority or by a reasoned opinion. Parties shall be promptly notified of each proposed or final decision or order by the delivery to them of a copy of such decision or order in the manner provided by section 17A.12, subsection 1.

(2) Except as expressly provided otherwise by another statute referring to this chapter by name, any party may file an application for rehearing, stating the specific grounds for the rehearing and the relief sought, within twenty days after the date of the issuance of any final decision by the agency in a contested case. A copy of the application for rehearing shall be timely mailed by the presiding agency to all parties of record not joining in the application. An application for rehearing shall be deemed to have been denied unless the agency grants the application within twenty days after its filing.

[C75, 77, 79, 81, §17A.16]86 Acts, ch 1245, §518; 88 Acts, ch 1100, §1; 98 Acts, ch 1202, §18, 46