Hello. Is a construction to perm primary residence loan allowed to have two different rates under TRID rules? For example, during the construction phase a fixed rate and during the permanent phase an adjustable rate (ARMS)?

TRID has nothing to do with pricing your loans. TRID is a disclosure regulation. You design your products based on State law, then you figure out how to disclose them..

Yes, however...there will be those cases where the design must be changed due to the difficulty or cost of preparing appropriate disclosures. This is why it's so important for a regulatory compliance officer to be included in all loan product development task forces, committees, or other discussion groups. The sooner regulatory complications are ID'd, the longer you have to find an affordable work-around.