inferTIC

Capital cost estimating · AACE Class 5 · 4 · 3

AI Inference for Total Installed Cost.

A capital cost estimator for process plants that shows its working. A deterministic engine computes every figure from published methods, and every figure carries its source: book, edition, table, page, cost index and factor set.

Open the app sign-in required Read the method
Isometric line drawing of a process unit: a reactor, two shell-and-tube exchangers, a column and a pipe rack on a plot

Plain statement

An estimator you can audit line by line.

Give it a plant capacity, a sized equipment list, or an equipment list plus quantified bulks. It returns a costed estimate with a stated AACE class, a Monte Carlo confidence band, and a line-by-line trace back to a published source or a named company rate set.

Nothing is computed in the screen. The engine is a pure library: same estimate file plus same methods library gives the same result, to the cent, every time. The library is versioned; an estimate records the version it was computed against and flags a mismatch instead of silently recomputing.

It is not a closed-box estimator. There is no mechanical design engine and no hidden bulk synthesis. Class 3 quantities are supplied — imported, entered, or derived by pure geometry from coordinates you typed — and priced at rates you can see and cite.

Calculation chain

  1. Sizing parameterYour input per item. A warning if it falls outside the correlation’s validity.
  2. Purchased costLibrary correlation at its base year, or a vendor quote tagged as such.
  3. Material and pressure factorsFrom the record, multiplicative on purchased cost.
  4. EscalationCEPCI from base year to your cost date; the index rows used are snapshotted into the file.
  5. Location and currencyA location factor with a required note on override; your FX rate and date.
  6. Installed costLang, Hand, Guthrie bare-module, or your own percentages.
  7. Allowances and contingencyIndirects, EPCM, owner’s cost, contingency: defaults by class, editable.
  8. Total and bandSeeded Monte Carlo, triangular or PERT per line or group; the seed is stored.

Features

Built for the reviewer as much as the estimator.

Three modes, three classes

Class 5 from capacity and a published plant type. Class 4 from a sized equipment list. Class 3 from equipment plus quantified bulks priced at unit rates. No class better than 3 is ever claimed.

AACE 18R-97

A trace on every line

Click a line: purchased cost, factors, installation, escalation, location, currency, quantity. Each step shows its inputs, its output and its citation: book, table, page.

Results and trace

A library with provenance

Equipment correlations, capacity exponents, unit-capacity costs, factor sets, class bands and cost indices, each record citing edition, table and page, second-pass checked against the owner’s copy where the edition is to hand.

Methods library 2026.09

Risk that reproduces

Triangular or PERT ranges per line, area or estimate. Seeded Monte Carlo: the same seed gives the same P10, P50 and P90, and the seed is stored in the file.

Risk

Check, approve, issue

Draft to Checked to Approved to Issued. Leaving Draft freezes the results; reopening needs a reason and advances the revision. Comments and sign-offs land in the audit trail.

Review

Reports a reviewer can read

Basis of Estimate under AACE 34R-05 headings, calculation trace, sources and provenance, assumption register, benchmarks, reconciliation. Excel, PDF and WBS exports.

Reports and exports

AI assist, optional

Off by default. Hosted or local models propose a record pick, a quote extraction or a narrative draft; you confirm; the confirmation is audited. No number a model returns enters a calculation.

Model-agnostic

Runs where the data is

One HTML file that opens in a browser with no network. Estimates autosave locally and save as JSON. An optional Windows desktop shell stores files on disk.

Offline

The engine, in this page

Move the slider. The engine returns the figure.

This is the app’s own capacity-scaling function running on one checked library record. The page holds no arithmetic: it hands a capacity to the engine and shows the value, the warnings and the trace step exactly as the engine returns them.

Illustrative reference plant — not an estimate. Slider bounds are a page choice; the engine, not the slider, decides validity and warns when the capacity leaves the exponent’s published range.

Record
Source
Reference point

Trace step, as the engine returns it 

            

          

        

      


      

      

        
Published methods only

        
Every coefficient traces to one of these.

        
Equations and coefficients are implemented as methods and cited by edition, table and page. No publisher’s table is reproduced. No commercial cost data is bundled. This list is rendered from the library’s own source registry.

        
        
Superseded editions are kept in the registry so issued estimates recompute identically; they are not listed here. Full method: Method and sources. Does it reproduce the books it cites? Validation note.