A quantity is an amount of something that can be measured or counted, such as a length, area, volume, weight or number of items.
In quantity surveying, a quantity is the measured amount of an item of work, stated in a defined unit and multiplied by a rate to give its value. Under NRM2, and SMM7 before it, work is generally measured net as fixed in position, with allowances for waste, laps and similar factors left for the contractor to include in its rates. Where the quantities in a bill are approximate, the work is remeasured as it is carried out and paid for on the actual quantities. Common points to watch are:
- the difference between firm and approximate quantities
- whether a quantity is net or includes an allowance for waste
- the effect of a significant change in quantity on whether the rates still apply
Related terms: quantify, bill of quantities, remeasurement, unit of measure.
