How are finish grade tolerances defined and checked?

• A. Finish grade tolerances are not specified and are not checked
• B. Tolerances are checked by GPS only
• C. Tolerances are defined by the design and are checked by surveys and level checks
• D. Acceptable deviations from design finish elevations as specified; checked via surveys, grade rods, and level checks

Answer: (D)

Finish grade tolerances specify how much the actual finished surface can differ from the design finish elevations. They are defined in the project design or specifications as acceptable differences at specified points or areas. In the field, these tolerances are checked by conducting surveys against the design elevations, using level checks and grade rods to measure the current surface elevations, and comparing them to the design values. Any deviation beyond the stated tolerance indicates that adjustments are needed to bring the surface into specification. GPS alone isn’t sufficient for finish grade checks due to vertical precision limits; it’s typically used to establish control points rather than verify finish elevations. Therefore, the best description is that tolerances are acceptable deviations from design finish elevations as specified, checked via surveys, grade rods, and level checks.