What is a benchmark, and what is the Contractor's responsibility on site surveys and benchmarks?

A benchmark is a point of reference by which something can be measured. All other grade, lines, levels, and benchmarks necessary for the prosecution of the work shall be established and maintained by the Contractor.

The Contractor shall provide and maintain well-built batterboards at all corners. He shall establish benchmarks in not less than two widely separated places.

 

As work progresses, the Contractor shall establish benchmarks at each floor giving exact levels of various floors, and shall lay-out the exact locations of all partitions as a guide to all trades.