Chapter 2 recap
The words behind the drawing
The key takeaways from this chapter’s 3 lessons.
General notes
- General notes state the rules for the whole set: standards, materials, loads, tolerances, sequence and workmanship.
- Sheet notes and keynotes apply to one sheet or one element; general notes to all sheets they cover.
- Notes often carry requirements that never reach the model (welding method, splice positions, curing).
- When a note and a drawing seem to disagree, the contract's order of precedence decides; ask, don't choose.
Reading specifications
- Drawings show where and how big; the specification says what, how well, and how it is measured and paid.
- Specifications are organised in numbered sections: MasterFormat in North America, NBS or Uniclass-based in the UK, agency standards for highways.
- A typical section covers general requirements, materials (products), execution, and often measurement and payment.
- Concrete strength is written as f'c in psi (US) or as a strength class such as C30/37 (Europe); exposure classes add durability rules.
From specification to quantities
- Every specified class or grade that is priced differently needs its own quantity line.
- Measurement rules (the specification's measurement clause, or a standard method) decide what is counted and how.
- Model quantities are geometry; they become priced quantities only once grouped by the right properties and adjusted to the rules.
- Reinforcement, formwork and finishes are often measured from schedules and rules, not from the model.