The engineering lab.
Explore the evidence. Test a change. Understand the result. Interactive tools for learning how source revisions, quantities and review decisions connect.
DRAWING → DIMENSIONS → QUANTITY → DECISION
Follow a quantity back to its source.
Select a base, compare two fictional revisions, then test a different depth. The drawing, calculation and quantity register stay connected.
Fictional pump plinths P1–P4
P1 · L 2.000 m × W 1.500 m × D 0.300 m
Diagrammatic arrangement; not a setting-out drawing. All four bases share the same dimensions. Changing depth affects all four.
Try 0.35 m. Allowed range 0.10–1.00 m. Custom values are labelled WHAT-IF and do not change a source revision.
Calculation and quantity register
2.000 × 1.500 × 0.300 = 0.900 m³ per base
| Base | Source | Quantity (m³) |
|---|---|---|
| P1 | R02 | 0.900 |
| P2 | R02 | 0.900 |
| P3 | R02 | 0.900 |
| P4 | R02 | 0.900 |
Revision effect: +0.600 m³ across four bases. Assumptions: rectangular volume, no deductions, no wastage; reinforcement, formwork and excavation excluded. Variance = calculated − BOQ. Arithmetic is not engineering approval.
Read the complete BOQ method →OBSERVE / QUESTION / EXPLAIN
Spot the discrepancy.
Three short practice cases. Look at the evidence, choose the best explanation, then reveal the reasoning.
Evidence on the desk
FICTIONAL TRAINING CASE
Current drawing R02: four bases, each 2.000 × 1.500 × 0.300 m. The takeoff still cites R01 (depth 0.250 m), and its quantity is 3.000 m³.
What should the reviewer investigate first?
No client documents or actual project results are used.
FIVE CHECKS / A CLEAR NEXT ACTION
What is missing before issue?
Record the state of your checks. This self-assessment identifies gaps; it does not certify a BOQ or replace responsible review.
Answers stay in this page until you reload or clear them. The optional text download is created locally in your browser. No account, project name or upload is required.
PLAN / MEASURE / REPORT
Turn quantities into a progress view.
Compare planned and actual concrete volume at the same reporting cut-off. This is a single-item demonstration, not a weighted project dashboard.
Reporting inputs
Use the same scope, unit and cut-off for both figures. Measured quantities require their own evidence and acceptance. A quantity gap alone does not establish time delay or a completion forecast.
Progress against total scope
Bars show quantity ÷ total scope × 100. Gap = actual completion − planned completion, expressed in percentage points.