Built-Form Cost Tool · prototype · introduction
Open the tool

An early-stage cost model you can check line by line.

For estimators, quantity surveyors, developers and builders pricing a mid-rise or tower mixed-use building before there are drawings. Toronto first.

You describe the massing. The tool measures the building, builds each element from trade components, and gives you the same cost two ways: by element (where the money is) and by trade package (who is paid, and how much). Every quantity shows its formula and inputs.

⚑ The rates are draft. Do not price a job from these numbers.

On the example below, most of the trade cost rests on flagged placeholder rates that nobody has verified. The quantities are the part you can rely on today. Bring your own rates, or read the dollar figures as a demonstration of how the tool works.

Take the four-step tour Go straight to the tool

1Pick a building

Start from a preset and change what differs. A preset fills every input; the basic view shows the dozen that matter (lot, setbacks, side conditions, storeys, stepbacks, suite mix) and the rest are one click away. The 3D model is drawn from the same measured surfaces as the quantities, so the picture and the numbers cannot disagree.

This tour uses the reference building: .

Lot—
Gross external area—
Storeys above grade—
Suites—whole suites, fitted to the mix
Saleable residential—

GEA is measured to the outside face of the walls, party walls to the full extent of this project's construction. Saleable follows HCRA Directive 3.

The other presets ( in all)
Opens the tool on this building: the 3D model first, then the Areas tab under it (where the GEA goes, suites, floor by floor). Open this building →

2See the quantities, and how each is worked out

Every quantity is a sum of measured surfaces. Click one in the tool and it lists the surfaces behind it, each with its formula, and lights them up on the model. Here is one you can check on a calculator.

Party wall area:

Convention: party walls count to the full extent of this project's construction, each floor, both sides.

Some of the others on this building

Exposed wall, opaque—
Glazing—
Roof—
Parapets—
In-suite partitions—single face
Foundation concrete—

The tool reports quantities for this building, from envelope and partitions to doors, fixtures, excavation and backfill.

Opens the Quantities tab with party wall selected: its surfaces are highlighted on the model and the working is listed under it. Open the working →

3See cost by trade package, and where each rate comes from

Each element is an assembly of components, and each component carries a trade. Summed by element you get the elemental estimate; summed by trade you get tender packages in MasterFormat order. Both come from the same lines, so the two totals always agree. Rates are entered on the package side, in the unit that trade quotes in.

—trade cost, low to high rates · draft · the tool's single figure is · of it rests on placeholder rates

Every rate carries its status and source. Yours always wins over the rate set, and is marked as yours. SME given by the cost expert · list from a cited list or tender · ⚑ update a rough placeholder, unverified.

The packages on this building (draft figures)

Add-ons on top of the trade total

Every add-on percentage is itself a flagged placeholder, and each can be overridden in the tool.

Opens the Cost tab on By trade package. Open a package to see its items, rates and sources, and type your own rate. Open the packages → By element

4Re-cut a package to match how you buy

Package boundaries vary by region and by builder. The built-in Toronto draft is read-only: copy it as your own template, then move a whole trade or a single item from one package to another. The estimate total does not change; only who carries the scope does.

Example:

—
—

Each package opens to a scope checklist: every item is included, excluded or by others, with a note. Marking an item excluded never takes its cost out of the estimate; it stays listed, because things get lost. Scope sheets (CSV) exports every package's checklist with quantities and no prices, to issue with tender packages.

Opens the same Cost tab. Use Copy as my template above the package table to start editing. Easiest at half a screen or wider. Open the package editor →

What is solid, and what is draft

Solid

  • The quantities. Every quantity rule has a test with the expected value worked out by hand, and the working shown in the tool adds back to each quantity.
  • The area breakdown adds back to GEA, on every preset.
  • Element and package totals reconcile after any package edit, because both are sums of the same component lines.
  • The measurement conventions are the cost expert's and are stated: GEA to the outside face, saleable on HCRA Directive 3, areas by use to exterior faces.
  • Nothing is hidden. An item in the model is always listed under some heading, even at zero cost.

Draft

  • The rates. Placeholders are rough estimates made by an AI assistant, unverified, and flagged ⚑ wherever they appear.
  • The add-ons (general conditions, fee, insurance, contingency, escalation) are placeholder percentages.
  • Assumptions that move cost are listed in the tool. This building uses .
    Show them
    • Presets and assemblies are illustrative: lot sizes are common ones, the stepbacks are not any city's bylaw, and wall and slab build-ups are first drafts.
    • Not yet reconciled against real project takeoffs. That is the next milestone.
    Open the tool

    It opens on the reference building. Change the preset or any input, switch between metric and imperial, and enter your own rates under Cost → By trade package. It works at phone width for reading; editing packages is easier at half a screen or wider.