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MEET OUR TEAM

With over 25 years of experience in the engineering field, Mark Sipos has built a reputation for his technical expertise, innovative problem-solving, and strong client relationships. Mark launched his career at The Kachele Group following his graduation from The Pennsylvania State University. In 2013, the firm’s Pittsburgh office transitioned into Keystone Structural Solutions, where Mark has continued to thrive. In November 2023, he took on the role of President and owner, solidifying his leadership and vision for the company’s future.

Mark is deeply committed to providing clients with thoughtful, creative solutions to complex design challenges, and he values the trust and long-term relationships he cultivates with each of them. His extensive experience spans a wide range of projects, but he is particularly passionate about the restoration of historic buildings, forensic engineering, expert witness testimony, and the design of wood structures. His engineering expertise is backed by his licensure as a Professional Engineer (PE) in 15 states, including Colorado, Connecticut, the District of Columbia, Indiana, Iowa, Louisiana, Maine, Maryland, Massachusetts, Michigan, North Carolina, New Hampshire, Pennsylvania, Texas, and Wisconsin.

Outside of his professional work, Mark is an active member of the South Fayette Board of Standards and dedicates time to coaching youth sports, including a travel softball team and a soccer team. His leadership extends beyond the office, where he is committed to shaping the community and fostering the next generation of athletes.

Mark Sipos, PE

PRESIDENT

Rhonda joined the company in 2013 when it began as Keystone Structural Solutions. She has continued in the broad role as office manager. She is a graduate of Penn State with a degree in Public Relations and Communications. Prior to graduating she studied architectural engineering and grew up with a background in construction.

She comes with a diverse background which aided in her new role at KSS which includes supporting the business side of operations. Although Keystone Structural Solutions was formed from a previous entity, all of the time and business management software needed to be set up and put in place. Rhonda joined as that process started and was part of implementing those solutions.

Things are a lot calmer than they were in 2013, but the job is diverse and brings changes daily which suits her personality.

Rhonda enjoys working with children, starting her day with a quality cup of coffee and ending the day with red wine and a friend!

Rhonda Moscollic

OFFICE MANAGER

Marc joined KSS in 2014 as a project engineer. He is responsible for managing all structural aspects of a project from start to finish. Responsibilities include design and detailing of steel, masonry, concrete, and wood structures. He also has experience writing specifications, structural BIM implementation, with client coordination, shop drawing review, and construction administration duties. Marc has performed structural design for commercial, retail, educational, residential, prison, and medical facilities for both new, renovation, and forensic project types.

Marc's favorite type of projects are multi-story steel frame buildings in which he can implement BIM and 3D structural design software to design and detail construction documents. My favorite projects while at KSS have been Chartiers Valley High School/Middle School, Riviera at PTC and Boardwalk I & II. Other interesting projects include California University of Pennsylvania Convocation Center, Middlesex College South Hall, Latrobe Education Center for Westmoreland County Community College, Somerset County (NJ) Social Services Building and the Operations and Maintenance Building for Alcosan.

In his free time, Marc appreciates spending time his family. He also enjoys fishing the many trout streams in PA, camping, landscape photography, and music.

Marc Peterson, PE

SENIOR LEVEL PROJECT ENGINEER

Karen has an extensive clerical background. She is a retired federal government employee with 20 years of service in this area. Karen gained experience in the engineering field as an employee at Dotter Engineering for many years. Her employment with Keystone Structural Solutions started in 2021 when she was asked to join the company as an administrative assistant after her husband, Bill, passed away.

In her spare time, she enjoys traveling, driving her Mustang convertible, and spending time with family and friends.

Karen Mayer

ADMINISTRATIVE ASSISTANT

Tony is a seasoned engineering professional with over 39 years of experience in structural engineering and business management. He is the founder and former owner of Keystone Structural Solutions, where he led the company for 10 years. Currently, he serves as a project manager at Keystone Structural Solutions (KSS), assisting with managerial tasks and contributing his expertise to various projects.

Before founding KSS, Tony managed the Pittsburgh office of The Kachele Group for 15 years, honing his skills in leadership and client management. His diverse background uniquely positions him to provide top-tier structural consulting services to architects, contractors, developers, attorneys, and private owners.

Tony Moscollic, PE

FOUNDER, PROJECT ENGINEER

Mark started with The Kachele Group in 2003 and has continued with the firm through the transition to Keystone Structural Solutions and to the present day. He is currently a registered Professional Engineer in 7 states. He has over 3 decades of experience as a professional engineer. Mark enjoys the challenge of renovation projects in existing buildings that often get very complicated and require strong engineering skill as well as sound engineering judgement. Some of his favorite projects include the renovation of the existing Sewall Center into the new UPMC Events Center on the campus of Robert Morris University as well as 151 First Side in downtown Pittsburgh.

While not at work, Mark enjoys spending free time with his family, and keeping tabs on the local sports teams. He is also a long suffering fan of the University of Pittsburgh football programs, and enjoys attending their games, both home and away, as much as possible.

Mark W. Tayman, PE

SENIOR LEVEL PROJECT MANAGER

Jeff has a long history with this team. He was one of the first to work in the Pittsburgh office of The Kachele Group in 1996 as a consultant. Jeff now is the Senior CAD Manager at KSS.

After graduating from Triangle Tech, Jeff started his professional career working for New Port News Ship Building Company. Later, he worked at DRS Architects for many years and eventually became an independent consultant. He worked as a private consultant for several prominent Pittsburgh architects such as Don Gmitter, Sandra Hundley and several other architectural firms. While working under these architects, Jeff gained experience on the architectural side of design. He has brought this experience to KSS and is an invaluable second set of eyes during the design phase of projects. With an abundance of knowledge in computer aided drafting, he has authored many automated add-on programs for both AutoCad and Revit and has helped develop several of the KSS drafting standards. Jeff's experience and his efficient usage of computer aided drafting programs is what helps enable KSS to provide efficient and accurate drawings. Outside the office, Jeff enjoys mountain biking, wood working and spending time with his wife Carolina

Jeff Moran

SENIOR CAD MANAGER

Brad joined the KSS team as a Project Engineer in May, of 2019. With over two decades of structural engineering experience, he has worked on all types of projects, including new buildings and additions/renovations/restorations of existing structures. Brad has designed structures using concrete, steel, masonry, wood, and other materials. He is capable of providing all aspects of project delivery, from schematic design to construction administration. Brad enjoys being able to work on many different kinds of projects. Some of his favorites have been the new hospital design at UPMC Monroeville, the renovation/restoration of an existing structure for Blind & Vision Rehabilitation Services of Pittsburgh, and the new First Presbyterian Church of Girard. Most of all, Brad appreciates developing relationships with clients, and being able to help them to achieve their unique vision.

When not in the office, Brad loves spending time with his family; coaching his daughters' soccer teams and fostering rescue dogs. He also loves music; going to see shows with friends and playing bad guitar around a campfire.

Bradley Lechwar, PE

ASSOCIATE

Sue Grant, PE

SENIOR LEVEL PROJECT ENGINEER

Wafaa joined KSS in 2021, bringing valuable experience in structural engineering. She began her career designing concrete buildings for projects across Egypt, Saudi Arabia, and the Middle East, gaining expertise in large-scale, complex developments. Currently, she specializes in designing structures using steel, wood, and masonry, where she enjoys the creative challenges of integrating various materials.

Wafaa is passionate about delivering innovative and efficient design solutions that meet both technical and aesthetic goals. Outside of work, she enjoys spending time with her family, discovering new hobbies, and relaxing with music and reading.

Wafaa Dawod

STRUCTURAL DESIGNER

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