Yes. A waterproof flooring product does not remove the need to check the concrete beneath it. A slab that looks dry can still release moisture vapour, and excessive moisture can become trapped under the finished floor. The installer should check the selected product’s requirements for concrete condition, testing and any moisture control measures before installation.
Ask which test method and acceptance limits apply to your flooring and, if used, its adhesive. Keep the results with the product and installation records. If readings fall outside the permitted limits, address the source of moisture and agree on a suitable solution before covering the slab. The basement flooring guidance explains surface preparation and material choices; moisture assessment is a separate part of deciding whether the floor is ready.