VentScan vs spreadsheets
A spreadsheet is a flexible manual calculator: it does exactly what you type, cell by cell, with no memory of where a value came from. VentScan is not a spreadsheet. It reconciles HVAC sources across revisions, recalculates consequences from written, versioned specifications, and records each decision in a Proof Pack. The spreadsheet trusts whatever you paste in; VentScan ties every number back to its source and proves how it was reached.
| Dimension | Spreadsheet | VentScan |
|---|---|---|
| Where values come from | Typed or pasted by hand; origin not recorded. | Read from HVAC sources and linked back to them. |
| Calculation logic | Ad-hoc formulas, editable in any cell. | Written, versioned specs, deterministic and tested. |
| Units | By convention; easy to mix up silently. | Carried explicitly; missing units are rejected. |
| Revisions | Saved as separate files; diffs are manual. | Entities matched across revisions, changes surfaced. |
| Uncertainty | A number is a number; maturity is invisible. | Maturity shown — an estimate is labelled, not hidden. |
| Audit trail | Cell history at best; intent is lost. | Append-only Proof Pack: source, consequence, approval. |
01What a spreadsheet does well
Spreadsheets are unmatched for flexibility. They are immediate, every engineer knows them, and they will model almost anything you can express in formulas. For a one-off calculation or a quick sanity check, nothing is faster.
That flexibility is also the limit. A spreadsheet does exactly what the cells say and keeps no record of where the inputs came from, whether the formula matches an agreed method, or whether a pasted figure was an estimate. When a revision lands, reconciling it is manual, and the reasoning behind a number lives in someone's head.
02What VentScan does differently
VentScan reads HVAC values from the project sources rather than having them typed in, and keeps each value linked to where it came from. Consequences such as cooling load and capacity margin are recalculated from written, versioned specifications — the same inputs always give the same result — with units carried on every value and missing units rejected.
When a new revision arrives, VentScan matches entities across versions and surfaces what changed instead of leaving you to diff two files by eye. Each decision is sealed into an append-only Proof Pack holding the source values, the recalculation and the engineer's approval. The current cooling-load calculation is a v1 estimate pending engineer review, and it is labelled as such rather than presented as final.
03From a private file to a provable decision
The practical difference shows up months later. A spreadsheet answers "what is the number"; VentScan also answers "which sources produced it, what method was used, and who approved it" — the questions that matter when a decision is challenged long after it was made.
When to use a spreadsheet
For quick exploration, a bespoke one-off model, or a method VentScan does not yet support, a spreadsheet is the right tool. Its flexibility is genuinely useful, and VentScan does not try to replace ad-hoc calculation.
Reach for VentScan when a number needs to trace back to its sources, stay consistent across revisions, and be provable later — when the calculation is part of a decision someone will rely on.