Our Staff

Carl R. Petrus, PE, MBA

 Carl is the owner and principal of Petrus  Engineering. He brings a wide array of design and manufacturing  experience to meet the needs of your capital project. Carl was a  senior process engineer with Air Products in Trexlertown, PA, a  maintenance manager with H.B. Fuller Co. in Paducah, KY, and a plant  manager with Southdown/Medusa Cement Co. in Wampum, PA.  He is an active  member in the National Society of Professional Engineers and was ASHRAE  trained in HVAC design.  He is also a former ASTM member, for both the  cement and concrete technical sub-committees (C-1 and C-9).  He earned a  bachelor's degree in chemical engineering from Penn State and an MBA  from the University of Pittsburgh.  He is a registered professional  engineer in PA, OH, N.J., and FL.  

Earl T. Coffin, PE

Earl is a licensed professional  Electrical Engineer that has a broad amount of experience and expertise  in the field of electrical and lighting design.  Earl has been  responsible for the electrical design at Petrus Engineering since 2006.   He was trained in the US Navy, in the field of radar and electronics,  and served our country overseas.  He was awarded a bachelor's degree in  Electrical Engineering from Y.S.U.  His work history includes Pratt  & Whitney Aircraft, US Steel, the Edward J. DeBartolo Corp., and  Pascoe Engineering.  He currently serves on the Mahoning County  Electrical Review Board.

Heather L. Hawryliak

Heather  is an architectural designer at Petrus Engineering. She specializes in  commercial building design and enjoys using her creative talents to  produce cost effective and efficient architecture. She graduated from  Butler Community College with a degree in Architectural Drafting and  Design. Heather has been designing at Petrus Engineering since 2011. 

Jeffrey Holes


Jeff is both a Senior Project Manager and an Architectural Designer with over 25 years of Design and Construction experience. Jeff was the owner of a design-build firm, specializing in church projects, which brings a very unique design perspective that is both practical and cost effective.  He has also worked for multiple Architectural and Real Estate Development firms in the Western Pennsylvania region.  Jeff has earned a Bachelor of Arts Degree in Architecture from Almeda University in 2006.  

Joshua B. Petrus


Josh is responsible for MEP (HVAC, Electrical, and Plumbing) engineering design, as well as complete Land Development submittals for Petrus Engineering. He specializes in Stormwater Modeling and has completed a wide array of stormwater management system designs including multiple NPDES permits.  His engineering design priority is to balance our clients’ budgets with all of the various code and agency requirements that are a reality in today’s environment.  He is a graduate of Youngstown State University, with a BS in Physics and a Minor in Mathematics, and was also a graduate student in the Physics Department at the Ohio State University.  He has been with Petrus Engineering since 2015.