O'Brien Mechanical, Inc. II is a family-owned, full-service Plumbing/Piping/HVAC contractor that self-performs a wide range of plumbing and piping installation work for commercial projects throughout the Greater Bay Area. Headquartered in San Francisco, OBMI's professional staff and trades people deliver full design, construction, and fabrication for complex plumbing, piping, and HVAC systems. First established in 1970 as O'Brien Mechanical and later changed to O'Brien Mechanical, Inc. II in 1998, today, OBMI employs over 90 union-affiliated and administrative employees generating well over $18 million in annual revenue. Our company advocates innovative engineering, advanced technology, quality craftsmanship, maximum efficiency, minimum waste, on-time scheduling and excellent customer service from beginning to end. Some of the Bay Area's most reputable building owners, managers, architects, engineers, and general contractors have been entrusting their plumbing/piping/HVAC systems to OBMI for over half a century.