Guide 8 · design codes

Rule pack format

A guide for councils, estate developers, body corporates, consultants and anyone who wants a set of planning or design rules checked against a Plotlay project. Version 1, 14 October 2026.

What a pack is

A rule pack is a list of checks Plotlay runs against a drawn project: a setback, a height, a site coverage, a fence height, a door width. Each check reports one of:

Plotlay ships packs for the Australian states, New Zealand, England, Ireland, the US, Canada and accessibility. Anyone can write their own as JSON, YAML or CSV and import it into a project (Design codes, Import a pack), or have an AI agent connected to Plotlay build one from a document.

A project keeps a copy of each pack it uses, at its version. A later check gives the same answer until someone chooses a newer version.

A small example

{
  "id": "seaview-estate",
  "name": "Seaview Estate design guidelines",
  "kind": "template",
  "jurisdiction": "Seaview Estate",
  "version": "2026.1",
  "published": "2026-03-01",
  "source": "Seaview Estate Design Guidelines, March 2026",
  "source_url": "https://example.org/seaview-guidelines.pdf",
  "disclaimer": "The developer's design approval is still needed.",
  "rules": [
    { "id": "front-setback", "title": "House front setback", "ref": "4.1",
      "each": "dwellings", "metric": "front_setback_mm", "op": ">=", "limit": 6000, "unit": "mm",
      "tolerance": 200, "note": "Porches may sit 1.5 m forward of the building line." },
    { "id": "fence", "title": "Front fence height", "ref": "6.2",
      "each": "fences", "where": { "front": true }, "metric": "height_mm", "op": "<=", "limit": 1200, "unit": "mm" },
    { "id": "colours", "title": "Roof and wall colours", "ref": "5.3",
      "each": "site", "op": "check", "note": "From the approved palette only." }
  ]
}

Pack fields

Rule fields

op: "check" is for what a drawing can't measure (overlooking, overshadowing, materials, waterproofing). It is listed once, as UNKNOWN, for someone to check by hand. Put the figures in the note.

What can be measured

Only a height someone measured or entered counts: drawing defaults never pass a rule.

Facts the drawing doesn't hold: params and limit_from

Declare what a person must enter for the project:

"params": [
  { "id": "wa_r_code", "label": "R-Code density", "type": "select", "options": ["R20", "R30", "R40"] },
  { "id": "zoning_front_setback_mm", "label": "Front setback in your zoning code", "type": "number", "unit": "mm", "help": "From your local zoning code" }
]

Then a rule's limit can come from it:

• A table by a choice: "limit_from": { "param": "wa_r_code", "values": { "R20": 6000, "R30": 4000 } }
• Bands by a number or a site figure: "limit_from": { "metric": "site.site_area_m2", "bands": [[300, 3000], [900, 4500], [null, 6500]] } (up to and including 300 m²: 3000; up to 900: 4500; more: 6500)
• The figure itself, for a template where the number comes from a local code: "limit_from": { "param": "zoning_front_setback_mm" }

applies_if limits a rule to some cases: { "param": "nsw_zone", "in": ["R1", "R2"] }, { "metric": "site.site_area_m2", "between": [450, 100000] }, { "param": "storeys", "op": ">=", "value": 2 }.

Until a fact is entered, its rules report UNKNOWN and say which fact they need. The common facts building_height_mm, wall_height_mm, storeys, gfa_m2 and car_spaces are shared by every pack.

YAML

The same fields:

id: seaview-estate
name: Seaview Estate design guidelines
version: "2026.1"
source_url: https://example.org/seaview-guidelines.pdf
rules:
  - id: front-setback
    title: House front setback
    ref: "4.1"
    each: dwellings
    metric: front_setback_mm
    op: ">="
    limit: 6000
    unit: mm
    tolerance: 200

Quote operators (">=") and versions ("2026.1").

CSV

One rule per row. Pack details go on # key: value lines above the header:

# id: seaview-estate
# name: Seaview Estate design guidelines
# version: 2026.1
# source_url: https://example.org/seaview-guidelines.pdf
id,title,ref,each,where,metric,op,limit,unit,tolerance,note
front-setback,House front setback,4.1,dwellings,,front_setback_mm,>=,6000,mm,200,
fence,Front fence height,6.2,fences,front=true,height_mm,<=,1200,mm,,
colours,Roof and wall colours,5.3,site,,,check,,,,From the approved palette only.

where: role=outbuilding;status=proposed. limit: 3000, 2..10 for between, a|b for in. limit_from, applies_if and params: JSON in the cell, with quotes doubled.

Versions and updates

• A project copies the pack at its version when it is chosen. Checks use that copy.
• Importing the same id at the same version replaces it. A new version is only used when someone chooses it (the app asks; the connector takes upgrade: true). The version used before is kept in the pack's history.
• A pack saved to a library is never changed: a change is a new version.
• Every compliance report lists the packs and versions it used.

Rules an AI agent enters

An agent connected to Plotlay can build a pack from a document it has read (create_rule_pack, update_rule_pack, import_rules). Each rule it enters is marked "needs review" until a person confirms it in the app (Design codes, Rules, Confirm). Until then, reports say: "Includes rules entered by an AI agent and not yet reviewed."

Good practice for authors

• Cite a clause in ref and a link in source_url for every rule.
• Never guess a number. If a figure depends on something you can't settle, use limit_from with a param, or op: "check" with the figures in the note.
• Say in the note what the check simplifies (an average of neighbours' setbacks, a formula, an exception).
• Give each version a date, and say which amendment of the source it reflects.