With little market demand for new office and civic buildings, AC Martin Partners is jump-starting its housing subsidiary by acquiring Pasadena-based residential architecture firm Togawa & Smith Inc.

In its 100-year history, AC Martin has designed landmark civic and office buildings across Los Angeles. But with developers shifting their attention to residential projects, the firm is repositioning itself.

“Firms always have to adapt to where the dollars are going,” said Christopher C. Martin, AC Martin’s chief executive. “Urban housing is coming of age in Los Angeles, and it’s a trend we feel is here to stay.”

AC Martin is buying Togawa & Smith in an all-stock deal and merging the firm with its residential subsidiary, to be renamed Togawa Smith Martin Residential. The acquisition is expected to close within the next month.

The amount of stock received by principals Glenn Togawa and Tim Smith in the parent company AC Martin Holdings Inc. was not disclosed. Both men will be named to the firm’s board.

Besides the new residential subsidiary, AC Martin Holdings will include architecture firm AC Martin Partners Inc. and Consulting Architects & Engineers Inc., the company’s build-to-suit practice.

AC Martin has already jumped into L.A.’s frenzied housing market. The firm is doing design work for a project that will turn the former Subway Terminal Building into lofts and is also working on the $1.8 billion Grand Avenue project, which has significant residential components.

Martin said bringing experienced residential designers was important, especially as it relates to potential litigation. “The trick to doing condominiums is that you have to have good clients and top-notch people,” he said. “You have to understand how to handle the litigious nature of the future owners of your project.”