Method
Open Talamh is building the first open, parcel-level atlas of land held by Catholic Church entities in Ireland. Every parcel traces back to a primary record, and every parcel carries a confidence grade. The method is being piloted in County Louth before it is extended to other counties and, later, to State bodies.
Principles
- Every claim links to a folio, deed, register entry or published document.
- Every parcel carries a confidence grade, so uncertainty is visible rather than hidden.
- The method, code and list of entities are published, so anyone can re-run or challenge the work.
- The map states facts and sources. Interpretation lives in separate, clearly labelled commentary.
- Releases are versioned with a changelog, and anyone can submit a correction.
What counts as “the Church”
The Catholic Church is not one legal owner. Open Talamh defines the entities it tracks and publishes those definitions.
| Class | Typical legal holder | Where names come from |
|---|---|---|
| Dioceses (26) and parishes | Diocesan trusts, named clerical trustees | Charities Regulator, diocesan directories |
| Religious congregations and orders | Trustee bodies, companies limited by guarantee, named trustees | Charities Regulator, CRO, AMRI membership |
| Schools | Patron trustees, boards of management, congregational trusts (e.g. Edmund Rice Schools Trust) | Department of Education school lists, patron bodies |
| Health and care | Voluntary hospital companies, congregational holding companies | HSE Section 38 list, CRO |
| Lay Catholic bodies | Companies, trusts | CRO, Charities Regulator |
Each parcel is assigned one ownership tier:
- Legal title: A Catholic entity or trustee is the registered owner on a folio.
- Beneficial interest: Title is held by individuals or a company in trust for a Catholic entity.
- Control without title: For example, patronage of a school on State-owned land, or a long lease.
- Former holding: Sold, transferred to the State, or handed over under redress agreements since 2002.
Confidence grades
| Grade | Evidence | Shown on the map as |
|---|---|---|
| A | A Land Registry folio names a Catholic entity as registered owner | Confirmed |
| B | A folio names individuals or a company, and a second source confirms they hold in trust for a Catholic entity | Confirmed via trustee |
| C | Registry of Deeds evidence only | Probable |
| D | Use, signage or a heritage record suggests Church ownership; title not yet checked | Unverified lead (not counted in totals) |
| E | Held since 2002 but since sold or transferred | Former holding |
The first Louth map is built entirely from open data, so every point on it is currently a grade D lead.
How ownership is established
The ground truth is the Land Registry folio: a mapped parcel with a named registered owner. About 93% of the State’s land area is registered. A Names Index search returns every folio registered to one exact name in one county, so the unit of work is name × county, not parcel.
- Collect the legal name of every diocese, parish, congregation, trust and school body, with every variant (prefixes such as “Trustees of”, Irish-language forms, abbreviations, former names). Keep extending it until a full round of checking new folios produces no new names. The list is published with a version number.
- Every search is logged, including those that return nothing. Each folio returned is pulled for its owner, burdens and location.
- Every church, convent, school and institution is looked up on the free Land Registry map to find its folio. Any site whose owner isn’t on the name list reveals a missing name. The share of known sites already found in step 2 measures how complete the search is.
- For land with no folio, the Registry of Deeds is searched by townland and by grantor and grantee name. These results get a lower grade.
- Every parcel is graded using the A to E scale above.
- A random sample is double-checked by a second researcher, totals are benchmarked against published figures (such as the 2009 panel valuations and RTÉ’s 800-property Christian Brothers portfolio), and each major entity is sent its list of parcels for a right of reply before publication.
Known blind spots
- Beneficial ownership registers for trusts and companies are not public, so trusts are only visible where a second source links trustee to beneficiary.
- Folios show legal title, not leases, licences or covenants.
- Trustee names change over time, so each folio is recorded with the date it was retrieved.
Data sources
Location data is plentiful and open, while ownership data is closed and paid. So the work of this project is to bridge the two data sources.
| Source | What it gives | Shows ownership? | Access |
|---|---|---|---|
| Land Registry folios (Tailte Éireann) | Registered owner, burdens, parcel map | Yes, the ground truth | Paid per search and per folio; free map search for folio numbers |
| Registry of Deeds, Henrietta Street | Deeds since 1708, by grantor and townland | Clues | In person, by appointment |
| OpenStreetMap | Churches, convents, religious land, schools, graveyards | No | Free (ODbL) |
| National Inventory of Architectural Heritage | Historic churches, convents, presbyteries and schools, with original and current use | No | Free |
| Department of Education school lists (primary, post-primary) | Every school with its ethos and location | No (the patron is not always the landowner) | Free |
| Valuation list (Tailte Éireann) | Rateable properties with use, area and location | No; places of worship are often exempt | Free |
| Charities Regulator register | Legal names of dioceses, parishes, congregations and trusts | Names only | Free |
| Companies Registration Office | Companies, directors, former names | Names only | Search free; documents paid |
| Ryan, McAleese and Mother and Baby Homes reports; Industrial Memories | Institutions, operators, dates | No | Free |
| Townland and county boundaries | Statutory boundaries | No | Free (CC BY) |
| Residential Property Price Register | Sale prices since 2010 | No | Free |
| INSPIRE cadastral parcels (Tailte Éireann) | Parcel shapes without owners | No | Licence to be confirmed |
See the reading list for the reports, journalism and research behind this method.
Publishing and licensing
Data is published under an open licence (CC BY 4.0, with layers derived from OpenStreetMap under ODbL), alongside the code, the entity list and a changelog. Folio boundary maps are subject to Tailte Éireann copyright, so until republication is agreed, parcels are published as points with folio numbers, which anyone can look up. Open Talamh maps organisations, not private individuals, and gives every major entity a right of reply before publication.