Operational bills

Operational bills are a tendering document for estimating costs prepared by architects that describes a construction project in terms of the operations (which include labour and plant) needed to build it. This form of document contrasts with that of bills of quantities in which such tendering and estimation is limited to the materials in the completed work. Operational bills have the advantages of enhancing communication between design and production, enabling realistic tender pricing, and making the preparation of critical-path analysis easy for the contractor. Operational bills were proposed and developed by Edward Skoyles  at Building Research Establishment in the 1960s. Priced-activity schedules of the NEC Engineering and Construction Contract are a modern related form, prepared by the contractor.