We are A.G. O’Brien

A.G. O’Brien Plumbing Company was founded in 1934 by Irish Immigrant, Adam George O’Brien, or more commonly known simply as A.G..
A.G. O’Brien built this company focused primarily on residential plumbing, heating, and sheet metal work. A.G.’s vision was to deliver top-notch customer experience and to place a strong emphasis on providing a quality product with unmatched craftsmanship.
In 1971 the A.G. O’Brien Company was taken over by Derrill Adatte Sr.. Under Derrill, the company expanded its residential division and developed a commercial plumbing, heating and ventilation division. Derrill Sr. ran the company until 1982 before passing it onto his son, Derrill John. In 1999 Derrill John added a fire sprinkler division and relocated the ever-expanding business to the Hermantown Industrial Park, where the offices and fabrication shops remain to this day. The company is currently going through another family generational hand off, to Chris Adatte.
