770-447-4555

350 Research Court Suite 130, Peachtree Corners, GA 30092

LEADERSHIP

OUR PHILOSOPHY

Our Philosophy is to provide a high level of engineering expertise for our clients through the active participation of the principals in the design process. Principals are assigned the lead role in each discipline and will be actively involved in the project for its complete duration. Each project receives personal attention in the design of mechanical systems from one or more of the firm’s principals from project inception through the design process to the construction completion of the project.

PE, LEED AP

Thom Wille joined JSA as a Mechanical Engineer in 1995 and has over 35 years’ engineering experience in project management and mechanical system design.

PE, LEED AP

Mike joined JSA as a mechanical engineer in 1999 and became a Principal of the firm in 2010. He manages both HVAC and fuel system projects.

Brad joined JSA in 1992 and has over 30 years’ experience with consulting engineering firms designing mechanical systems.

PE

John has been with JSA since August 1987. He was promoted to an Associate position in 2005 and serves as the firm’s Senior Associate, Plumbing Engineer.

NICET Level II

Rick has been with JSA since 1992 and is currently the Senior Associate of the firm. His responsibilities include the fire protection design of commercial projects.

LEED AP BD+C

Cat has been a key member of Johnson, Spellman & Associates since October of 1998. She is now one of JSA’s valued Senior Associates. 

Diedrich joined Johnson, Spellman & Associates, Inc. in 2010 and has been a key member of the team for more than 10 years.

770-447-4555

350 Research Court Suite 130, Peachtree Corners, GA 30092

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