Lump sum calculation

Commentary at page 117 of the FIDIC Guide to the 4th Edition is recommended. The Guide explains that some of the Contractor's overhead costs are included in the rates for items of work and others are included in separate items in the Bill of Quantities. Changes to the actual quantities may mean that the overhead content of items which have paid is not appropriate to the actual overhead costs incurred by the Contractor. In order to calculate any adjustment the Engineer will need to obtain information from the Contractor, or would have to make his own assessment. Any calculation must take into account any adjustment which has already been made under another Sub-Clause and only applies to any increase or decrease in excess of 15% of the Effective Contract price. The Sub-Clause starts with a reference to the situation "on the issue of the Taking-Over Certificate for the whole of the Works". It is also necessary for the value of variations and other adjustments to have been agreed in order to make the Sub-Clause 52.3 calculations. Any additional payment or deduction would then be made in the next payment certificate after the figures have been agreed or determined. - See more at: