Standard of care: what it is, what it is not, and why contract language matters

One-line orientation

The standard of care asks whether an architect used the ordinary skill and care of a reasonably prudent peer in the same locality, time, and circumstances. It does not promise a perfect result.

Key points

• Definition: The standard of care is the ordinary skill and care expected from a reasonably prudent peer under similar circumstances — measured against what a reasonably prudent architect in the same locality would do at the same time.

  • It is relative, not absolute: it varies by community and evolves over time.
  • It is not a promise of perfection.
  • It is not a warranty or guarantee of any specific outcome.

• Where it appears:

  • NCARB Model Rules of Conduct and the AIA Code of Ethics both reference it.
  • AIA B101 Section 2.2 governs the architect’s standard of care (without using the phrase explicitly).
  • AIA C401 Section 2.1 mirrors this language for architect-consultant agreements; the two contracts should use identical standard-of-care language to avoid gaps.

• Raising the standard — the liability trap:

  • Clients may push to amend contracts with language like:
    • “Use your best efforts”
    • “Perform to the highest standard of architectural practice”
    • Guaranteeing or certifying results beyond what the architect can know
  • These modifications raise the standard of care above the ordinary benchmark → increased liability exposure.
  • Critically: Promises above the ordinary standard of care can create liability that professional liability insurance may not cover.

• Standard of care vs. warranty/guarantee:

  • A warranty or guarantee is a promise of a specific result — if the result is not achieved, the architect is liable regardless of how carefully they practiced.
  • Standard of care only requires reasonable professional judgment; if the architect applied that judgment, they have met the standard even if an outcome was imperfect.

• Other raising-the-SoC traps:

  • Taking on contractor responsibilities inadvertently raises the SoC by suggesting the architect controls means and methods.
  • For BIM, define who may use the model, what they may rely on, and how information is shared. The project agreement controls whether the model or drawings are the relied-on documents.
  • Off-the-cuff verbal assurances or hyperbolic language in correspondence can be construed as raising the standard.

• Spearin Doctrine connection:

  • In owner-contractor disputes, the Spearin Doctrine means the owner impliedly warrants the adequacy of owner-provided plans and specifications to the contractor. It protects a contractor who reasonably follows defective owner-provided documents, but it does not erase the architect’s potential liability to the owner for negligent design.

Confusions / comparison

	Standard of care	Warranty / guarantee
What it promises	Reasonable skill and professional judgment	A specific, definite result
Benchmark	Reasonably competent architect, same locale, same time	Absolute outcome
Insurable under E&O?	Yes — this is exactly what E&O covers	No — E&O does not cover promises above SoC
Liability if things go wrong	Only if the architect was negligent (below the SoC)	Strict — regardless of care exercised
Example language	”Architect shall perform services consistent with the professional skill and care ordinarily provided by architects…"	"Architect guarantees / warrants / certifies results”
Exam trigger	”Reasonable,” “prudent,” “same locality"	"Best efforts,” “highest standard,” “guarantee,” “warrant”

Related

→ pp-insurance-types — why E&O covers negligence but not above-SoC promises
→ pp-claims-made-vs-occurrence — how and when E&O coverage is triggered
→ pp-surety-bonds — contractor obligations (distinct from architect professional liability)