Refixing of rate

You are referring to the 4th Edition 1987 of the Contract for Works of Civil Engineering, Sub-Clause 51.1 (a) allows the Engineer to issue an instruction to increase or decrease the quantity of any work included in the Contract. The rate which the Engineer agrees or fixes under Sub-Clause 52.2 would only apply to the varied quantity (increased or decreased). The original quantity is not part of the Variation and would be paid at the original rate. - See more at: