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How it works

From construction drawings to a reviewed estimate

Eight stages, each with a named owner. AI-Assisted Drawing Intelligence can highlight what is on the drawings; an estimator verifies it, measures, structures and checks the work, and reviews every output before it is issued.

Follow the workflowSee examples
  • AI-assisted, verified
  • Controlled calculation
  • Human reviewed
Process sheet · drawing to deliverable8 stages
  1. 01DrawingsWho: Estimator
  2. 02ReviewWho: Estimator
  3. 03Drawing intelligenceWho: AI-assisted · estimator verifies
  4. 04TakeoffWho: Estimator
  5. 05StructureWho: Estimator
  6. 06CalculationWho: Controlled calculation
  7. 07ReviewWho: Human review
  8. 08DeliverableWho: Estimator
EstimatorAI-assisted suggestionControlled calculationHuman review

01 · What we work from

The project's own drawings and documents

Every quantity starts on a drawing. Which documents matter depends on the service: a quantity takeoff needs the plans and specification, a specialist package its discipline drawings, a tender the full issued set.

Before anything is measured, each sheet is registered with its title and revision.

Drawing register
Illustrative Example
Illustrative drawing register
SheetTitleRev
A-101Ground floor planRev B
A-200Front elevationRev B
A-301Wall sectionRev B
A-310Wall detailRev B
M-101Ventilation layoutRev B

  • Architectural drawings

    Plans, sections and elevations.

  • Structural drawings

    Foundations, frames and slabs.

  • Building services drawings

    Discipline layouts for specialist packages.

  • Construction details

    Build-ups, layers and junctions.

  • Specifications

    What each element is and how it is described.

  • Schedules

    Door, window, finishes and equipment schedules.

  • Tender documents

    Instructions, addenda and any pricing documents issued.

  • Existing takeoff

    Measured quantities to structure or check, where applicable.

Step by step

Eight stages, and who is responsible for each

Technology assists one stage and calculates another. People own the rest — and nothing reaches an output without an estimator's review.

  • Estimator
  • AI-assisted suggestion
  • Controlled calculation
  • Human review
  1. 01

    Drawing stage

    Receive and register

    The drawings and documents are listed by sheet, title and revision, so every later figure has a known source.

    Who
    Estimator
    Produces
    Drawing register
    In more depth : Receive and register
  2. 02

    Drawing stage

    Understand the scope

    The estimator reads the set for scope, checks each scale and raises gaps or ambiguities as queries before measuring.

    Who
    Estimator
    Produces
    Scope notes and queries
  3. 03

    Intelligence stage

    Drawing intelligence

    AI-Assisted Drawing Intelligence can highlight walls, rooms, openings and symbols. Each suggestion stays unconfirmed until the estimator checks it.

    Who
    AI-assisted · estimator verifies
    Produces
    Suggestions to verify
    In more depth : Drawing intelligence
  4. 04

    Takeoff stage

    Measure

    Confirmed elements are measured as lengths, areas, volumes or counts, each with its unit and drawing reference.

    Who
    Estimator
    Produces
    Measured quantities
    In more depth : Measure
  5. 05

    BOQ stage

    Structure the quantities

    Measured quantities are organised into work sections and described items, with units and references kept.

    Who
    Estimator
    Produces
    Structured items
    In more depth : Structure the quantities
  6. 06

    Estimate stage

    Calculate

    Where the service includes an estimate, each item is multiplied by an explicit rate from the controlled rate set, and lines roll up into totals.

    Who
    Controlled calculation
    Produces
    Estimate build-up
    In more depth : Calculate
  7. 07

    Review stage

    Validate and review

    Units, sources and rates are checked, every line is traced to its sheet, and an estimator reviews the result for scope and completeness.

    Who
    Human review
    Produces
    Review record
    In more depth : Validate and review
  8. 08

    Review stage

    Deliver

    The reviewed output is issued with its drawing references, queries and recorded assumptions.

    Who
    Estimator
    Produces
    Reviewed output
    In more depth : Deliver

03 · Drawing intelligence

AI-Assisted Drawing Intelligence: it suggests, the estimator decides

On a drawing, AI-Assisted Drawing Intelligence can highlight elements and information worth checking. It is a starting point for the estimator, not a result.

What it does

  • Highlights walls, rooms, openings and symbols on a drawing
  • Surfaces information for the estimator to look at
  • Leaves every suggestion unconfirmed until it is checked

What it does not do

  • Measure or issue quantities on its own
  • Decide what is in scope
  • Set rates or make commercial decisions
  • Replace the estimator's review

Sheet A-101 · before and after

Illustrative Example

Before · as received

Illustrative plan as received: two rooms, an internal door, two windows and a furniture symbol, with nothing marked.ROOMOFFICE

After · suggestions to verify

Illustrative plan with five suggestions marked S-01 to S-05 for the estimator to verify: a wall, a room, a door, a possible door and a symbol.ROOMOFFICES-01S-02S-03S-04S-05
Illustrative log of suggestions and the estimator's decision on each
RefEstimatorResult
S-01ConfirmedW-01 · External wallSuggested: Wall
S-02ConfirmedA-03 · Room floorSuggested: Room
S-03ConfirmedD-01 · Door setSuggested: Door
S-04CorrectedA window, not a doorSuggested: Door
S-05RejectedFurniture — not measuredSuggested: Fixture
Illustrative Example — not a real project. Suggestions are not quantities: only what the estimator confirms or corrects is measured.

04 · Measurement

Four kinds of quantity, each with its source

Whatever is measured — a length, an area, a volume or a count — the record keeps the drawing, the dimensions, the unit and whether it has been checked.

  • Length

    m
    Ref
    W-01 · External wall run
    Drawing
    A-101 · Rev B
    Dimension
    16.00
    Quantity
    16.00 m
    State
    Reviewed

  • Area

    m²
    Ref
    A-03 · Room floor
    Drawing
    A-101 · Rev B
    Dimension
    8.00 × 5.60
    Quantity
    44.80 m²
    State
    Reviewed

  • Volume

    m³
    Ref
    CON · Foundation concrete
    Drawing
    S-101 · Rev B
    Dimension
    16.00 × 0.60 × 0.40
    Quantity
    3.84 m³
    State
    Confirmed

  • Count

    nr
    Ref
    D-01–03 · Internal door sets
    Drawing
    A-101 · Rev B
    Dimension
    3 × 1
    Quantity
    3 nr
    State
    Re-counted
Illustrative Example

05 · Structure

Measured work, organised into sections and items

Quantities become described items under work sections. Each item keeps its reference, description, unit, quantity and the drawing it was measured from — the same structure as a quantity schedule or bill of quantities.

Quantities to items

Illustrative measured quantities and the bill items they become
MeasuredQtyBill item
W-0141.60 m²E.1Blockwork wall
Lintels3 nrE.2Lintels over openings
A-0344.80 m²M.1Floor finish
F-0127.20 mM.2Skirting
Anatomy of a structured item · BOQ-01Illustrative Example

E · MasonryWork section

Item
E.1
Description
Blockwork wall, 100 mm, external wall W-01
Unit
m²
Quantity
41.60
Drawing ref.
A-301 · Rev B
  • Item — Reference under its section
  • Description — Written from the drawings and specification
  • Unit — Stated, never inferred
  • Quantity — 16.00 × 2.60, measured
  • Drawing ref. — Where it was measured

06 · Calculation

Controlled calculation, with the working shown

Where a service includes an estimate, each figure is built from an explicit quantity, its unit, a stated formula and a rate from the project's controlled rate set.

Calculation chain · item E.1

Illustrative Example
  1. 1

    Quantity

    41.60

    Measured from W-01

  2. 2

    Unit

    m²

    Carried with the quantity

  3. 3

    Formula

    qty × rate

    Stated for the item

  4. 4

    Controlled rate

    rate E.1

    Explicit input from the rate set

  5. 5

    Cost

    cost E.1

    41.60 m² × rate E.1

  6. 6

    Total

    Σ section E

    Rolls up to the estimate

  7. 7

    Validation

    • Unit match
    • Source recorded
    • Rate source
    • Reviewed
Illustrative Example — not a real project. The rate is named rather than valued: rates are explicit inputs from the project's controlled rate set, not generated automatically.

07 · Review and traceability

Any figure can be followed back to the drawing

Review checks the output against its sources. Revisions, open questions and assumptions are recorded, so the basis of every figure is stated.

One item, traced

Illustrative Example

  1. Source drawing

    A-301

    Wall section · Rev B

  2. Item

    E.1

    Blockwork wall

  3. Quantity

    41.60 m²

    16.00 × 2.60 · W-01

  4. Output

    BOQ-01

    Section E · line E.1

  5. Review

    Reviewed

    Estimator sign-off

Recorded alongside the output

Revision · E.1 · Blockwork wall

Was 39.52 m² · Rev A

changed to 41.60 m² · Rev B

The item quantity follows the re-measured wall. The description and reference are unchanged.

Query · Q-02Open

Lintel detail not shown on the wall section.

A-301 · affects item E.2

Assumption · A-04Recorded

Typical lintel detail assumed until Q-02 is answered.

Recorded with the estimate

08 · Deliverables

What you receive

Illustrative Example

Each service ends in a defined, reviewed output. The sheets show document structure only — each links to a worked illustrative example.

See it applied

Follow the workflow through six worked examples

Each illustrative example takes one input through the process to a reviewed output — or compare the seven services to find the one that fits your drawings.

See the examplesExplore services