100 Years of Service

In 1915, Ed Peterson started a plumbing and heating company in Sonoma, CA. It wasn't long before the Peterson name became synonymous with integrity and meticulous craftsmanship. Now, with over 130 employees, Peterson Mechanical is a leading mechanical contractor serving the Greater Bay Area.

We are very proud of our legacy of experience; however, we never rest on our laurels. As fresh challenges emerge, Peterson will continue to explore new technologies, construction techniques, and building systems to deliver the best possible projects for our clients.

  • Born in 1890 and raised in Sonoma, Ed Peterson Opens his Plumbing and tinning shop at 438 First Street West (Yenni Building).
  • Peterson was a plumber and a dealer of tanks, pumps, water pipes, windmills and brass faucets. His customers included the State Department of Engineers, Vallejo Barracks, Buena Vista Winery, Sonoma State Home(Sonoma Developmental Center) and schools.
  • Ed returns from serving in WWI and forms a partnership with Gus Marcy, Marcy-Peterson Plumbers on Broadway (1921).
  • Marcy-Peterson partnership dissolves and becomes Peterson Plumbing and Tinning Shop (1939). Business moves to 120 West Napa Street.
  • Work at Sonoma State Home (hospital) includes the school and milk house.
  • Ed's nephew, Rich Peterson, joins the company after returning from WWII (1949), becoming the company's second generation of Petersons. Company moves to Broadway, building an expanded storefront with hardware, appliance and sporting goods departments. Name changed to Ed Peterson Heating and Sheet Metal Work.
  • Company diversifies to take on work at Humboldt State College (1956), Zellerbach Winery (1959), and Sonoma Valley Hospital (1952), the first of many medical facilities.
  • Company incorporates as Peterson mechanical Inc. (1957).
  • Ed Peterson passes away (1961).
  • Company moves to 254 First Street East and liquidates the hardware department, focusing on sheet metal, plumbing and heating, ventilating, and air conditioning (HVAC).
  • Projects include Sonoma State College cafeteria and PE building (1967) and Printed Circuit Manufacturing (1969).
  • Rich's son, Les Peterson, becomes the third generation of Petersons to join the company (1973).
  • Company becomes a Carrier Authorized Dealer.
  • Rich Peterson becomes president of PHCC (1977).
  • Projects include Federal Building and Courthouse in Santa Rosa, Jordan Winery (1977, Hillcrest hospital in Petaluma (1973), and Sonoma Valley Hospital Tower (1973)
  • Hidronic solar home project on the Westerbeck estate in Sonoma is featured on the cover of Sunset Magazine (1973).
  • Les's brother, Kris Peterson, joins the company.
  • CAD, 2D InteliCad and Quickpen technologies adopted.
  • Work is completed on multiple university campuses as well as Napa, Marin and Santa Rosa Junior Colleges.
  • Company moves to its current location at 21819 8th Street East (1999).
  • Kris Peterson leaves the company.
  • Design build and engineering departments open
  • Computerized estimating (2000)
  • Autodesk Fabricator 3D, Revit Capabilities and BIM Participation (2003)
  • Les's son, Scott Peterson, joins the company after completing college, becoming the fourth generation of Petersons in the business.
  • Safety director position created.
  • Rich Peterson passes away (2006).
  • Mike Titchenal, P.E., joins Engineering Department.
  • Les's nephew, Zach Brandner, P.E., joins company as a project manager.
  • Les Peterson becomes president of SMACNA (2007).
  • Company selected by LCI NorCal for lean company projects.
  • Detailing team includes 10 detailers.
  • Scott Peterson, Zach Brandner and Mike Titchenal join the firm's Leadership Team.
  • Over the past two decades, Peterson Mechanical Inc. has completed work on an extensive list of projects, including: Mondavi, Stags Leap, and Hall Wineries; SSU Darwin Hall; SRJC Culinary School; multiple Kaiser medical office buildings; Queen of the Valley Hospital; Marin County Correctional Facility; Santa Rosa Juvenile Justice Center; Green Music Center; Agilent Technologies; Medtronics; Bio Marin; and Sutter memorial Hospital (IPD Design-Assist).
  • Peterson Mechanical Inc. celebrates its 100-year anniversary.