Plans and Specifications
What the domain tests
Plans and Specifications tests the document set: location plan, site plan, floor plans, elevations, sections, details, schedules, specification, bill of quantities and contract conditions.
Core rules
- Drawings show size, shape and position; the specification states quality, materials, workmanship and testing; the bill of quantities quantifies and prices work.
- A prescriptive specification names materials and methods. A performance specification states the required result and lets the contractor propose a system.
- Schedules list doors, windows, rooms and finishes so information is not buried in drawings.
- Drawings must match approved documents and current revisions. Build only from the latest issued revision.
- Co-ordinate architectural, structural and services information and resolve clashes before construction.
Worked example
A drawing shows a 150 mm slab. The specification requires 25 MPa concrete, 20 mm aggregate, 75 mm slump and 7 days curing. A contractor proposes 20 MPa concrete. Reject it: the specification sets minimum quality, while the drawing sets geometry. The contractor should submit a mix design and cube test results for 25 MPa concrete.
Traps
- Treating the bill of quantities as a design document.
- Ignoring provisional sums or prime cost items.
- Working from a superseded revision.
- Assuming a scaled drawing overrides a written dimension.
- Missing a specification clause because only drawings were read.