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Photograph a room.
Get it measured, ducted,
and checked against G4.

Drop in a few photos. An agent estimates the room from what it can see, builds a measurable model, sizes the extract ducting the fixtures need, and runs every ventilation check in the New Zealand Building Code that a photograph can actually answer. It quotes the clause each time, and it tells you what a photograph cannot establish.

an estimate, not a compliance determination

Drop photos of one room

Two to six shots work best: one from each corner, and one straight at the window wall. JPEG, PNG or WebP. They go to the model and come back as a model; nothing is kept.

The model, from the photographs

The room, in metres

drag to turn it

The checks, with the clause quoted

Against G4/AS1

Every figure below is arithmetic on the estimate. The wording is quoted from the Acceptable Solution, 5th edition, 28 July 2025.

What it will not do

It estimates. It does not certify.

build an agent for your practice

How it works

Four steps, and none of them is a guess dressed as a number.

1 · It reads the photos

An agent estimates the room using objects of known size in frame, and it names which ones it used: a door leaf at about 1.98 m, a light switch at 1.0 to 1.2 m, a benchtop at 0.9 m, a brick course at 86 mm.

2 · It builds a real model

The estimate becomes walls, a floor plate and openings in the Pascal schema, which is MIT-licensed and open source. The same pipeline reads a real IFC file exported from Revit or ArchiCAD.

3 · It sizes the MEP

Extract rates come from the Code. Duct diameters come from ordinary practice at about 3 m/s, and the page labels that as practice rather than as a requirement, because it is.

4 · It checks, and it quotes

Net openable area against 5% of the floor. The 6 m span limit. The extract rate for every moisture fixture it can see. Each with the clause verbatim and the arithmetic shown.