In the past 34 years, Tustin, Calif.-based Largo Concrete has built a reputation as one of California’s most reliable specialty contractors.

A modest house set on an equally modest lot in tiny Pearl River, N.Y., north of New York City, was built in the early 1900s by Fred L. Holt, founder of what became Holt Construction Corp. It still is headquarters for the contracting firm that his grandson now leads.