Skip to main content

Structural Engineering

Our expertise in structural design and coordination is based on over 69 years of engineering buildings and related structures. Our clients rely on our ability to balance deadlines and budgets with the design insight required for structural work. We offer in-depth knowledge of current building codes, the ability to anticipate the unexpected, and creative insight that makes every project a success.


Jori Lemmon
Structural Manager, Principal
Jori Lemmon is a structural engineer with 20 years of experience in all construction materials and specializes in seismic design and construction practices. Jori is experienced with collaboration across multiple locations for project work and communicating with various disciplines. She has worked on numerous public and private projects, including military, health care, seismic retrofit, correctional and educational facilities. She serves the California State Board for Professional Engineers, Land Surveyors, and Geologists as a seismic subject matter expert. Her in-depth understanding of the codes has been pivotal to the success of design and construction on projects with the variability of the industry. Jori has established herself as a trusted advisor and team member with clients, designers, and contractors alike.

California Civil Engineer No. C72331
California Structural Engineer No. S5844

Washington Civil Engineer No. 52880
Colorado Civil Engineer No. 58366
Idaho Civil Engineer No. 19871
Michigan Civil Engineer No. 6201309517
Montana Civil Engineer No. 85860
North Dakota Structural No. 288848
Oregon Structural Engineer No. 90681
South Dakota Structural Engineer No. 15083


American Society of Civil Engineers (ASCE)
Structural Engineers Association of Central California (SEAOCC)
American Institute of Steel Construction

Subject Matter Expert for California Board of Engineers and Land Surveyors


BS Civil Engineering
California Polytechnic State University
San Luis Obispo, CA

Soon-Min Kwon
Director of Structural BD, Principal
Soon-Min Kwon offers 20 years of hands-on structural design and management experience. While he has worked on a range of commercial and educational projects, he has spent the more substantial part of his career focused on healthcare environments including medical office buildings, ambulatory surgery centers, cancer centers, hospitals and large medical campuses. His advanced understanding of OSHPD regulations, patient privacy needs and the imperative for keeping vital services running uninterrupted during projects all serve to make Soon-Min a highly valued partner to clients. His expert knowledge of Integrated Project Delivery has led to the successful delivery of several tenant improvements, seismic retrofits and hospital expansion projects for several prominent health providers.

California Civil Engineer No. C68633


Structural Engineers Association of
Central California (SEAOCC)
Lean Construction Institute (LCI)


MS Civil Engineering
UC Davis, Davis, CA

BS Civil Engineering
Kyung Hee University, Seoul, Korea

Siegfried’s Featured Structural Projects

City of Stockton, City Hall Relocation Phases I & IIStockton, CA

Santa Clara Valley Water District, Coyote Pumping Station WarehouseSan Jose, CA

San Joaquin Regional Transit District (RTD), Downtown Transit CenterStockton, CA


Higher Education
Parking Structures
Public Assembly
Public Works
Tall Buildings


Structural Engineering
Construction Engineering
Secure Design
Restoration & Renovation
Forensic Analysis
Seismic Assessment
Seismic Upgrade
Feasibility Studies
Sustainable Design
Blast Design
Historic Renovation
Structural Peer Review
Structural Plan Checking
Damage Assessment
Performance-based Engineering
Vibration Analysis & Design
Building Code Assessment

Project Delivery Experience

Design-Build (DB)
Design Bid Build (DBB)
Integrated Project (IPD)
Public-Private-Partnership (3P)
Construction Manager at Risk (CMAR)

Siegfried Engineering