NPK bill of quantities
The CRB’s standardised item catalogue (NPK) supplies the standard texts used to tender construction work; tendering with it lets you compare bids item by item.
Definition
The benefit is comparability: because every bidder quotes the same item texts, a price difference is a price difference and not a matter of interpretation. Without standardised items you compare apples with pears — and notice at the final account.
The items carry through to the account: tender, award, measured quantities and final invoice follow the same numbering. That is exactly the requirement on the software — it must import the catalogues and keep the numbers.
Where to read it
What the software must be able to do
Check: import of the catalogues in the current edition, item numbers continuous from tender to final invoice, and comparison of several bids per item. A program that knows items only as free text loses the comparison.
Checked Aug 2026
More terms under Construction and planning: Cost plan BKP / eBKP Quantity surveying SIA project phases Time-and-material reports