Descriptive specifications are a hybrid of which two types of specs?

• A. Performance and prescriptive
• B. Descriptive and reference
• C. Proprietary and open proprietary
• D. Unit cost and unit-in-place

Answer: (A)

Descriptive specifications blend prescriptive detail with performance criteria. They describe the material or system by its physical characteristics and required quality, while also specifying the performance outcomes and the tests or standards used to verify those outcomes. This means you’re not locking in a single brand or installation method (as a purely prescriptive spec would), but you are detailing the exact properties the material must have and the performance it must achieve. The combination ensures the product meets specific attributes (like composition, finish, or thickness) and also performs to defined standards or test results. For example, a descriptive spec for a concrete mix might require certain aggregates and cement types, a specified slump, and a target compressive strength, along with the test method and acceptance criteria. That mix of explicit material properties and measurable performance is why descriptive specifications are considered a hybrid of performance and prescriptive approaches.