CanIBuildHere

How CanIBuildHere Works

A transparent explanation of our data sources, methodology, limitations, and what our reports are (and are not).

What this is

CanIBuildHere is an automated planning-data screening tool. When you drop a pin on the map, we combine live public endpoints, imported official map layers, stored development-plan text and cached official planning documents to identify relevant planning and property context. We present this information in a plain-English report with source links, so you can verify any finding independently.

What this is not

  • Not a planning decision or Section 5 declaration
  • Not a substitute for professional planning advice
  • Not a site investigation, ecological survey, or flood risk assessment
  • Not a guarantee of planning permission or a formal opinion on viability
  • Not a replacement for pre-planning consultation with the local authority

Our reports are screening tools for early-stage decision-making. They help you understand what the publicly available data shows before you spend money on drawings, consultants, or site purchases.

Data sources

Depending on the location and project type, we query or consult the following public data sources:

Zoning and land use

  • Council development plan zoning polygons (imported from official open-data portals per authority)
  • MyPlan.ie generalised zoning (national fallback where council data is unavailable)
  • Development plan policy text (semantic search against stored plan corpus)

Method: Deterministic spatial intersection (PostGIS)

Flood risk

  • Council development plan flood-zone layers (Zone A and Zone B where available)
  • OPW Flood Relief Scheme benefitting areas

Method: Deterministic spatial intersection

Nature conservation

  • NPWS Special Areas of Conservation (SAC)
  • NPWS Special Protection Areas (SPA)
  • NPWS Natural Heritage Areas (NHA) and proposed NHAs (pNHA)

Method: Distance-based proximity (15km radius for AA screening context)

Heritage and archaeology

  • Council Record of Protected Structures (where published as open data)
  • National Inventory of Architectural Heritage (NIAH)
  • National Monuments Service SMR records
  • Architectural Conservation Areas (council layers)

Method: Spatial intersection and proximity

Environmental and ground conditions

  • GSI Groundwater Vulnerability
  • GSI Bedrock Aquifer classification
  • GSI Subsoil Permeability
  • GSI Landslide Susceptibility
  • GSI Bedrock Geology and Quaternary Sediments
  • GSI Karst Features
  • GSI Geothermal Suitability
  • EPA CORINE Land Cover
  • EPA Licensed Facilities
  • EPA DWWTS Risk Zones
  • EPA Source Protection Areas
  • EPA Radon Risk areas
  • WFD River and Groundwater Body Status

Method: Real-time ArcGIS REST API queries (point-in-polygon)

Planning history

  • LGMA National Planning Application Database (ArcGIS feature layer)
  • Local-authority planning references and available case links
  • An Coimisiun Pleanala appeal cases and available official documents

Method: Reference normalisation, spatial matching, relationship classification and document extraction where available

Roads and access

  • OpenStreetMap road network (via Overpass API)
  • Building footprints for ribbon development estimation

Method: Real-time spatial queries, road-geometry-refined dwelling counting

Administrative boundaries

  • Tailte Eireann (OSi) boundary datasets: townland, electoral division, local authority, municipal district, Gaeltacht

Method: Point-in-polygon lookup via ArcGIS REST

How findings are classified

Our report distinguishes three categories of finding:

Deterministic spatial facts

"Your site intersects Flood Zone A" or "SAC is 340m from the pin." These come from direct polygon intersection or distance calculation. They are verifiable and objective.

Policy-derived context

"Galway County Council requires a genuine local housing need." These come from development-plan rule extraction and are labelled with their policy reference. They are factual statements about what the plan says, not predictions about outcomes.

Derived assessments

"Wastewater: ground looks favourable" or "Ribbon pattern: 3 mapped clusters." These combine multiple data layers into a composite indicator. They are clearly labelled as derived and are not a substitute for site-specific investigation.

Document-derived statements

Findings from official planning files retain the document title, authority, source link and page where available. Statements are classified as applicant or observer claims, technical submissions, inspector assessments, planning-authority decisions or final appeal decisions. A claim is not presented as an established finding merely because it appears in a document.

Coverage and confidence

We screen locations across all 31 local authorities in Ireland. Coverage quality and update frequency vary by dataset, authority and document portal:

  • Council zoning and local-plan layers are used where a suitable official dataset is available
  • National or generalised datasets may be used as a fallback and are labelled accordingly
  • Planning registers and appeal portals differ in document availability, structure and reliability

Where our report uses fallback or generalised data, this is clearly labelled in the finding with wording like "MyPlan generalised zoning fallback." Council-tier data is labelled with the specific plan name and period.

Limitations

  • Spatial data has inherent positional accuracy limits. Pin placement should be on the actual site, not an adjacent road or field.
  • Development plan layers reflect the plan as adopted. Variations, material alterations, and draft plans in progress may not be captured.
  • Planning history is sourced from the national dataset, which may lag council records by weeks.
  • A map pin, address or locality match does not by itself prove that an application belongs to the selected property. Reports distinguish subject-property, wider-landholding, adjoining and nearby context using the available matching evidence.
  • Official PDFs may be unavailable, removed, scanned, incomplete or poorly indexed. We extract native text first and use OCR only when needed; either method can misread a document.
  • Mapped boundaries and building footprints do not establish legal title, rights of way, ownership or the lawful use of a property.
  • Environmental data from GSI, EPA, and NPWS reflects national-scale mapping. Site-specific conditions (e.g. actual percolation results) may differ.
  • Ribbon development counting uses building footprints and road geometry as a proxy. Manual verification on the ground is always required.
  • Our risk classification (High/Medium/Low) is a screening indicator, not a professional planning assessment.

Use of AI

The core spatial analysis in every CanIBuildHere report is deterministic - it uses GIS polygon intersection, distance calculation, and rule-based logic. No AI/LLM is involved in determining whether your site is in a flood zone, near a protected structure, or subject to a specific development plan policy.

AI-assisted services may be used for bounded tasks including:

  • The "Ask a follow-up" feature, using the report's loaded planning and source context
  • Plain-English summaries and structured extraction from planning text
  • Policy-text retrieval and optional interpretation of building imagery or document text

AI output is constrained by loaded source material and validation rules, but it can still be incomplete or wrong. Source links and document provenance are therefore retained so material findings can be checked against the official record.

Attribution

CanIBuildHere uses publicly available data from official Irish government sources. We attribute each finding to its source in the report. Key attributions:

  • Council zoning layers: individual local authorities, licensed under CC BY 4.0 (or equivalent open licence)
  • Environmental data: Geological Survey Ireland (GSI) open data services
  • Nature conservation: National Parks and Wildlife Service (NPWS)
  • Planning applications: LGMA National Planning Application Database
  • Boundaries: Tailte Eireann / Ordnance Survey Ireland open data
  • Road network: OpenStreetMap contributors (ODbL)
  • Flood data: Office of Public Works (OPW) and council development plan layers