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Design and Professional Liability

Expert Required Unless Common Knowledge Exception Applies

Kenneth Slavens | May 30, 2025

water spraying weakly from a fire hydrant in a residential neighborhood

This relatively straightforward dispute arising from the development of a subdivision is a reminder of the significant role experts and the common knowledge exception have in claims involving design professionals. See Cranes Creek, LLC v. Neal Smith Eng'g, Inc., 291 N.C. App. 532 (2023).

Facts of the Case

In the Cranes Creek lawsuit, a developer planned to purchase land in North Carolina to develop into a residential development. As part of its due diligence, the developer asked an engineer, who had been engaged to perform other work, to opine about water flow to a fire hydrant. The engineer responded with a somewhat qualified answer, saying that the minimum "fire flow" to a preexisting fire hydrant met "minimum fire flow requirements."

After purchasing the property, the developer learned that additional water lines would need to be installed to satisfy "minimum flow requirements for fire suppression." To recover the additional costs, the developer filed suit against the engineer, alleging four different theories of recovery—negligence, negligent misrepresentation, breach of contract, and breach of implied warranties—though eventually the claims were reduced to only negligence and negligent misrepresentation.

The developer had two experts testify against the defendant (the engineer); however, neither said the defendant's services violated the acceptable standard of care.

Eventually, the defendant filed a motion for summary judgment, which is appropriate where there is no genuine issue as to any material fact such that a party is entitled to a judgment as a matter of law. The trial court granted the motion for summary judgment.

The Court's Analysis

To succeed in pursuing its claims, the North Carolina Court of Appeals noted that the developer must establish the standard of conduct or care through expert testimony. The expert assists the jury in discerning whether the defendant's professional performance or conduct did not conform to the standard of care and, as a result, was in breach of that duty and the proximate cause of the claimed damages.

The exception to the need for expert testimony is the common knowledge exception. The court noted that this exception applies if "the common knowledge and experience of the jury is sufficient to evaluate the defendant's compliance with the standard." However, where the common knowledge exception does not apply, and the plaintiff fails to establish the professional standard of care through expert testimony, there may be no negligence proven.

The North Carolina Court of Appeals held that this dispute did not fall within the common knowledge exception. Absent viable expert testimony, the developer's claims failed.

Lessons Learned

An important takeaway from this opinion is that parties, like our developer here, must realistically evaluate and understand the professional advice received. If advice is qualified or conditional, the appropriate course is to seek further clarification or additional opinions as necessary.

If you find yourself in a professional liability claim, especially one involving technical expertise, like the design professions here, the outcome often hinges on expert testimony. All parties must be prepared with qualified experts. Courts will not let cases proceed to trial if there is no expert evidence of negligence, except in the rarest of cases where the issue is within common knowledge exception.

Experts are critical to establishing the standard of care. However, not just any expert will do. The expert must clearly articulate the opinions to be offered in support of the plaintiff or the defendant. Though the "common knowledge exception" is a viable theory, it is rarely successful in technical cases.


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