Budget vs Actual

Budget vs actual is the bridge between preconstruction planning and operational cost control.

The Basic Model

The approved estimate becomes the budget baseline
Actual costs are recorded over time against cost groups
Darwin compares the two to identify movement and risk
Commitments provide an intermediate layer between planned and actual costs

Variance Layers

With commitments in place, variance can be analyzed at three levels:

Layer	Comparison	Business Question
Procurement	Commitment vs. Baseline	Did we buy at the planned price?
Execution	Actual vs. Commitment	Did final costs match the commitment?
Total	Actual vs. Baseline	What is the overall project variance?

Why It Matters

Budget vs actual analysis helps teams identify whether cost movement is driven by:

market shifts
design changes
scope growth
execution inefficiency
assumption mismatches

Best Practices

Baseline only reviewed and accepted estimates
Group budget and actuals in a consistent cost-group structure
Review variance regularly, not only at the end
Feed lessons back into modules and pricing practices
Use the active baseline as the reference — not an arbitrary historical estimate