Who we are

Orndorf & Associates, Inc. (O&A) is a structural engineering and design firm located in suburban Philadelphia, PA with branch offices in Greenville, DE, and Rehoboth Beach, DE. We are an award-winning, client-oriented firm that combines the extensive in-depth experience of a larger engineering firm with the personalized service of a small firm.

Benefits of working with us

  • Our principal has over 40 years of diverse structural engineering design experience.

  • We are registered in 26 states, plus the District of Columbia, and will travel to meet our client’s needs.

  • We have a wide-range of experience in designing all building types.

  • We have experience in steel, concrete, timber, masonry, as well as sheeting and shoring during construction and foundation underpinning.

  • We have experience with seismic design for earthquake-prone areas of the country.

  • We have experience with high-wind design and with FEMA requirements for the design of shore properties built on pilings.

  • We have experience with solar panel installation, ICF/Lite Deck, and SIPS.


  • Above all we are responsive to our clients needs and serve them in a professional manner.

  • Building strong relationships with our clients is an important aspect of our corporate culture as evidenced by a high percentage of repeat business.

  • On all projects we stress the importance of design excellence with an emphasis on detailed construction documentation. This results in a low percentage of change orders during construction.

  • We strive to exceed technical, financial and scheduling goals on all project deliverables.

  • Each project is completed in a timely manner, within its written scope of services, and within its budget.

  • We attribute our success to the company’s policy of assigning a new project to a dedicated project manager who is involved from schematics to final construction under the guidance and leadership of our principal.

Meet the team


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