Irvine’s Impac Mortgage Holdings Inc., which buys mortgages as investments, is looking to start making loans itself with the acquisition of Florida's Pinnacle Financial Corp.

A subsidiary of Impac is buying Pinnacle's business of making loans on its own and through brokers.

Terms of the deal were not disclosed.

Pinnacle was founded in 1988. It offers mortgages to first-time homebuyers. The company counts more than 133 branches in 26 states. It has 15 branches in California, according to the company’s Web site.

The deal marks a change in strategy for mortgage investor Impac. To date the company has focused on buying and selling Alt-A loans, which are one step above subprime loans in terms of risk.

Impac had been looking to diversify, said Joseph Tomkinson, chief executive of Impac.

With the acquisition “we immediately become a nationwide retail lender with specific expertise in the prime agency business including the first-time homebuyer and emerging markets,” he said.

A newly formed division called Impac Home Lending is set to run the just-acquired business. The division will include Pinnacle’s cofounders, who will act as managing directors.

The transaction is expected to close by the end of May.