Estimating, Plan Reading, and Project Scheduling
What this domain tests
This domain checks whether you can read a drawing, convert what you see into quantities and money, and sequence the work realistically. Expect scale-reading items, quantity takeoffs with waste, unit conversions, and critical-path scheduling.
Plan reading and takeoff
- Scale: 1/4 in. = 1 ft means 1 in. on paper is 4 ft. Measure with the stated scale, and note that enlarging a print does not change the stated scale unless the bar scale grows with it.
- Read all views: plan, elevation, section, and detail must agree; the detail wins on how a specific assembly is built.
- Takeoff by system: measure once, price once. Record lengths, areas, and counts in the unit you will buy them in.
- Waste factors: framing lumber about 5–10%, roofing 10%, siding 10%, concrete 5%.
- Conversions: 1 cubic yard = 27 cubic feet; 1 sq ft at 1 in. thick = 1/12 cu ft.
Scheduling
Use the critical path method: forward pass for early dates, backward pass for late dates, and the difference is float. The path with zero float is critical - any delay there moves the completion date. Tie inspections, material lead times, and cure times into the logic, not into a list of notes.
Worked example
Four tasks: A (3 days) precedes B (4 days) and C (5 days); both precede D (2 days). Paths are A-B-D = 9 days and A-C-D = 10 days. The critical path is A-C-D at 10 days, and B carries 1 day of float. Pushing B back a day costs nothing; pushing C back a day pushes the whole job.
Traps that cost marks
Reading an area scale as a length; forgetting waste so the last wall is short; counting a window twice in two views; adding float to a critical activity; scheduling an inspection before the work it releases.