We have a loan secured by the borrower's primary residence with the proceeds being used to refinance existing loan (also secured by primary residence) with additional funds to construct a shed on the property to store equipment used in his lawn business. I know that this is HMDA reportable. Would you report this as home improvement because the shed is being constructed on the same land as his personal residence or as a refinance because the "home improvement" is being used for commercial purposes?

I'm in the refinance camp. See this thread for a robust discussion on this topic Similar discussion.

Agree with TM as we would not report a HI when it is for storing of his business equipment.