Stirrett Johnsen
Mechanical Contractors
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Kitsap’s Largest, Most Trusted Mechanical Contractor

Since 1972

The Stirrett Johnsen Advantage

Stirrett Johnsen, Inc. has grown to become the largest mechanical contractor in Kitsap County and among the largest and most trusted in the Pacific Northwest. With staff located in Silverdale, Renton, and Yakima, we efficiently serve all markets within the State of Washington, in addition to select out-of-state projects.

We rely on industry knowledge, depth of experience and unmatched craftsmanship to deliver quality systems on time and within budget. Because of this track record, the vast majority of our work is with repeat customers.


 silverdale corporate office

5555 NW Westgate Rd
Silverdale, WA 98383


(360) 692-6128

Featured Projects


PremierE on pine

This 40-story, design build, 386 unit apartment building includes 5 stories of underground parking, 4 stories of above ground parking and one floor of retail space. 


Vulcan Block 34,

Amazon Headquarters

Block 34 consists of 2 steel-framed buildings with a 5 story glass connector. The total footage includes 550,000 square feet of Class A office space and street level retail, extensive rain-fed water features, plus 213,800 square feet of parking.  



St. Anthony hospital

St. Anthony Hospital is a state of the art, 256,000 square foot 80 bed hospital in Gig Harbor, Washington, owned and operated by Franciscan Health System.  

Key Markets


Our work in the healthcare sector includes regional medical centers, out-patient clinics, urgent care, medical office buildings, specialty clinics, and dialysis treatment.  These projects often have specialized equipment with specific mechanical needs such as hazardous waste, medical gas, and redundancy of critical systems.  We are certified in medical gas and infection control and have experience working in occupied medical facilities.  We understand the complex federal, state, and local codes that are unique to healthcare facilities.



We have a successful history in the K-12 plan spec market constructing dozens of schools in Washington State.  We also participate in public and private higher education facilities such as Seattle University, Pacific Lutheran University, University of Puget Sound, University of Washington, Olympic College, and many more.


High-rise residential

& senior living

In Seattle, these tend to be large scale projects ranging from 10 to 43 stories. Design considerations for noise, peak use, and efficiency are critical to a successful project.  Large scale senior living facilities such as Timber Ridge and Heron’s Key are more recent senior living projects.


community & recreation

Our work includes fitness center projects like Pro-Sports, YMCA Silverdale and Sumner, and UPS Aquatic Center.  These type of projects often have specialized needs based on high peak usage such as swimming pools and large spas.


special projects

These projects vary in scope from small repairs to oddball diagnostics and small remodel projects.  We average approximately 500 special projects each year in addition to our major contract work.



Our engineers have depth of understanding specific to industrial processing and manufacturing to provide high quality and reliable industrial systems.  We also maintain a staff of employees with Rapidgate badges for easy access to Naval Base Kitsap.


water featureS

We have provided specialty equipment and piping for extensive water features all over the state of Washington. Some notable installations are the river feature at Amazon Block 34 and the City of Bremerton's Fountain Park.


Office Towers

We have been involved with construction of office buildings of all shapes and sizes.  Some of our more recognizable customers include Amazon, Microsoft, Facebook, Vulcan, and Boeing.  


  • Having worked with Stirrett Johnsen for over 10 years on numerous other Franciscan Health campuses, we were familiar with the exceptional quality of your field personnel, office staff, BIM detailing department and fabrication shop capabilities. We required a trusted, top-notch mechanical contractor to work with us on this (St. Anthony Hospital) project and Stirrett Johnsen was the perfect choice.
  • We consider SJI to be absolutely best in class in providing plumbing services and they are a preferred provider to GLY. Their ability to provide highly cost effective plumbing services with exceptional design and preconstruction support followed by high quality installation in the field is what we expect from SJI on each and every project.
  • I cannot say enough wonderful things about this company and the people who work for them. They are top notch. I would not hesitate to hire them for any job, no matter how large or small.