720-598-0774 info@rja-eng.com

Meet Our Engineering Team


Who We Are.

Founded in 2009, Ramirez, Johnson, and Associates was formed on the principles of providing engineering solutions with a customized approach that delivers the best value for every project. As a small firm, we can give each client and project the personal attention deserved. Licensed in Colorado and 13 other states, our engineers, commissioning agents, and designers are ready to take on projects ranging from $1,000 to $100,000,000, including commercial spaces, healthcare facilities, educational facilities, multi-family and high-end custom residential projects. RJA is M/WBE, DBE, SBE, EBE Certified.

Our Partners.

Darin Ramirez, PE

Darin Ramirez, PE

Founding Partner

As a founding principal of RJA, Darin provides experience attained since 2004 in the design, construction, and consulting industry.  He is involved in all aspects of the firm’s daily operations.  As designer, Darin’s passions include collaborating with owners and users to truly understand their needs, and providing design solutions that are efficient and appropriate for each clients.  Off the clock, Darin can usually be found chasing his kids, climbing, and skiing in the Rocky Mountains.

Education:
Bachelor of Science, Mechanical Engineering, University of Florida

Affiliations and Registrations:
Professional Engineer:  CO, KS, NC, OK, OR, TN, TX, WA, WY, MT, & UT

Certified Geoexchange Designer

LEED AP

Eric Johnson, CxA

Eric Johnson, CxA

Founding Partner

Eric’s passion for buildings and sustainable design directs the work of the firm and his construction and contracting background provides a practical perspective on each project. With two decades of experience, Eric is involved in either a design or commissioning role on every project and excels at leading talented engineers and designers towards solutions that are in the best interest of the client and the project. As a strong community supporter, Eric’s volunteerism through Junior Achievement helps to provide a positive and lasting impact on young people’s economic and entrepreneurship skills, career choices, and success.  During his free time, Eric enjoys skiing, hiking, golfing, and spending time with his family.

Education:
Bachelor of Science, Architectural Engineering, University of Colorado

Affiliations and Registrations:
LEED AP

Certified Commissioning Authority, CxA


Our Engineers.

Paul Plewczynski

Paul Plewczynski

Electrical Engineer

As an electrical engineer, Paul has amassed engineering experience in the Denver area since 2007.  His background includes roles on the owners’ team as well as on the consulting side of the industry.  Paul is responsible for spearheading RJA’s Revit/BIM collaboration with our clients, and he specializes in new and existing projects that require creative power distribution design.

Paul enjoys hiking, backpacking, and mountain biking with his wife and three kids.

Education:
Bachelor of Science, Electrical Engineering Technology, MSU Denver
Associates Degree, Computer Aided Drafting, ITT Technical Institute

Affiliations and Registrations:
ICT Design Fundamentals

Scott Zimmerman, PE

Scott Zimmerman, PE

Mechanical Engineer

Scott is a mechanical engineer with experience in the commercial and industrial sectors. Since 2010, his varied project background includes telescope observatories, college sports facilities, mineral processing plants, commercial kitchens, and breweries/distilleries. Scott is well versed in the BIM/VDC design process and is a proponent of 3D modeling software.

In his free time, Scott enjoys fourwheeling and exploring Colorado’s backcountry.

Education:
Bachelor of Science, Mechanical Engineering, University of Arizona

Affiliations and Registrations:
Professional Engineer: AZ, CA, CO, IA, ID, and UT
Member ASHRAE, former Chapter President
LEED Green Associate

Judah Katz

Judah Katz

Mechanical Engineer

Judah is a talented and detail-oriented individual with over a decade of mechanical and plumbing design experience in the residential, commercial, and light industrial sectors. His project experiences are comprised of a diverse group of industries including educational facilities, restaurants/breweries/bars, retail spaces, institutional housing, and higher education.  Technically, Judah is adept in the use of multiple energy modeling, BIM, and design softwares.  Family, music, and finding ways to enjoy the sun are his choices when not in the office.

Education:
Bachelor of Science, Mechanical Engineering, University of Alabama

Affiliations and Registrations:
Member ASHRAE

Chris Wood

Chris Wood

Mechanical Engineer

Chris began in 2012 as a mechanical and plumbing engineer acquiring experience in multi-family and light commercial construction. He has engineered and managed projects from 350-unit multifamily buildings to small office tenant finishes. Chris moved to Denver from Western NY in 2009 after graduating from Alfred State College. In his off time Chris enjoys biking, hiking, and spending time with his dog.

Education: 

Bachelor of Science, Mechanical Engineering Technology, Alfred State College

Theresa Gray, PE

Theresa Gray, PE

Electrical Engineer

Working in the electrical and lighting design industry since 2001, Theresa’s passion for lighting design and efficient power systems has helped shape countless projects.  Theresa is licensed professional engineer and active member of the Illuminating Engineering Society of North America.

Education:
Bachelor of Science, Architectural Engineering, University of Colorado, Boulder

Affiliations and Registrations:
Professional Engineer:  CO, WY, CT
IES
LEED AP

Nathaniel Morrison, EIT

Nathaniel Morrison, EIT

Electrical Engineer

Nate is an electrical engineer whose project portfolio includes power and lighting design throughout residential, commercial, light industrial, and municipal sectors. His favorite projects are those that benefit the community around them as well as those that refurbish historic buildings and places. Nate enjoys working closely with contractors and owners to find the best designs for their needs.  

In his free time, Nate enjoys long-distance running, backpacking, pottery, and traveling.

Education:
Bachelor of Science, Electrical Engineering, Colorado School of Mines

Ryan Liberman, EIT

Ryan Liberman, EIT

Mechanical Engineer

Ryan joined RJA as a mechanical engineer in 2020. His background includes a degree in Engineering Physics from Tulane University and his technical background includes designing HVAC systems in the New Orleans area. His hobbies include snowboarding, Ultimate Frisbee, and Rocket League.

Education:
Bachelor of Science, Engineering Physics, Tulane University

Nora Raine, EIT

Nora Raine, EIT

Mechanical Engineer

Nora’s background includes a degree in Mechanical Engineering from Iowa State University and experience designing mechanical systems in central Iowa. She relocated to Denver following after graduating to join the RJA team in 2021. She enjoys cooking, hiking, and skiing.

Education:
Bachelor of Science, Mechanical Engineer, Iowa State University

Charlie Shae

Charlie Shae

Business Manager

Charlie has worked as an Architectural Designer since she graduated in 2016, focusing primarily on multi-family residential, retail, and renovation projects, with an emphasis on affordability and energy conservation.  In her current role, Charlie focuses on business development, AR/AP, and financial projections.  Her eclectic background in research, design, project/process management facilitate her in streamlining approaches so that we continue providing the best service.  Charlie relishes her free time mountain biking, painting, reading, dancing, and sharing laughs with friends.

Education:
Bachelor of Science, Biotechnology, University of Nebraska at Omaha

Master’s of Architecture, University of Colorado Denver

Affiliations and Registrations:
LEED Green Associate

Andy Achtermann, PE

Andy Achtermann, PE

Mechanical Engineer

Andy has worked as a mechanical engineer since he graduated in 2012.  He specializes in a variety of residential, commercial, and industrial building system types including but not limited to: restaurants/bars, hotels, low to high-rise multi-family, schools, offices, and process design (steam and grow facilities).
In his free time, Andy enjoys traveling, golfing, baking, and brewing beer.

Education:
Bachelor of Science, Architectural Engineering, University of Colorado, Boulder

Affiliations and Registrations:

Professional Engineer, CO and AR

Member ASHRAE

Henry Furuta, EIT

Henry Furuta, EIT

Mechanical Engineer

Henry entered the MEP industry in 2018. He has designed mechanical and plumbing systems for a wide variety of projects across the country from sports stadiums to office tenant improvements, and enjoys 3D modeling. In his free time he spends his time playing Ultimate Frisbee, traveling, and flying.

Education:
Bachelor of Science, Mechanical Engineering, University of Texas at Austin

Shelly Achtermann

Shelly Achtermann

Electrical Engineer

Shelly has worked as an electrical engineer since 2018. She enjoys designing energy efficient power and lighting systems for commercial, industrial, and residential projects. Her project background includes multi-family, offices, restaurants/bars, schools, warehouses, and retail spaces. In her free time she likes to hike, garden, play with her dogs, and tend to her chickens.

Education:
Bachelor of Science, Biological Sciences, Colorado State University

Derek Wetch

Derek Wetch

Mechanical Engineer

Derek is a mechanical and plumbing engineer with design experience in the multi-family and restaurant sectors. He has a unique background as a field engineer, having served as both a Project Engineer and a VDC Engineer in Montana. Derek has proficiency with utilizing Revit and Navisworks through all stages of the design and construction process.

In addition to his full-time projects at RJA, Derek is pursuing a masters degree in Mechanical Engineering at the University of Colorado Boulder in a working-professional track. When not at work and school, his hobbies include backpacking, fly-fishing and backcountry skiing. An Arvada native, Derek is excited to use his skillset to build Colorado responsibly.

Education:
Bachelor of Science, Mechanical Engineering, Montana State University Bozeman
Masters of Science, Mechanical Engineering, University of Colorado Boulder (In progress)

Alex McPheeters

Alex McPheeters

Electrical Engineer

Alex has worked as an Electrical Engineer since graduating from Colorado State University in 2021. He has experience in industrial power engineering and a background in Mechanical Engineering. Alex moved to Colorado from Phoenix, Arizona for school, and in his free time he enjoys golfing, racing, and weightlifting.

Education:
Bachelor of Science, Mechanical Engineering, Colorado State University
Minor, Biomedical Engineering, Colorado State University

See What We’ve Been Working On

View some of the engineering projects our team has designed locally, in the state of Colorado, and across the country.  We’ve created solutions for commercial, retail, food service, multi-family housing, healthcare, renovation, hospitality, government, industrial, laboratory, and tenant finish projects.

Contact Our Denver Team

We consider projects of all sizes across the state of Colorado and beyond. Talk to our team to see if RJA is right for your next engineering project.

OUR CERTIFICATIONS

  • Professional Engineering
  • MBE, DBE, SBE, EBE
  • Member of the AABC Commissioning Group
  • CXA Certified Commissioning Agents
  • Certifiably Green Denver

OFFICES & CONTACT

3301 Lawrence Street, Suite 2
Denver, CO 80205
e: info@rja-eng.com
p: 720.598.0774