# Brick Schema

> Brick is an open-source, community-driven ontology that standardizes semantic descriptions of the
> physical, logical and virtual assets in buildings and the relationships between them. It is
> expressed in RDF/OWL with SHACL shapes and published under BSD-3-Clause. Brick 1.4.4 defines 1,428
> classes — 935 Point subclasses, 330 Equipment, 108 Location — joined by 79 object properties, under
> the permanent namespace https://brickschema.org/schema/Brick#. Brick is a specification you
> download and reason over locally, not a hosted service: there is no commercial API, no pricing, no
> sign-up and no rate limits.

Generated 2026-09-04 by API Evangelist from the published Brick artifacts. Brick publishes no
llms.txt of its own — https://brickschema.org/llms.txt and https://docs.brickschema.org/llms.txt both
return 404 (probed 2026-09-04).

## What Brick is

- [Introduction](https://brickschema.org/): What Brick is, and the problem it solves for building analytics.
- [Documentation](https://docs.brickschema.org/intro.html): The full Brick documentation — data model, model lifecycle, instance metadata, subsystem modeling, extensions.
- [Ontology browser](https://ontology.brickschema.org/): Class-by-class reference for every Brick term.
- [How Brick compares](https://brickschema.org/comparision/): Brick against other building metadata efforts.

## The ontology (the machine-readable contract)

- [Brick 1.4.4 — Turtle](https://brickschema.org/schema/1.4.4/Brick.ttl): The current stable ontology, 1.7 MB of RDF/OWL with inline SHACL shapes.
- [Brick 1.4.4 — JSON-LD](https://brickschema.org/schema/1.4.4/Brick.jsonld): Same graph as JSON-LD 1.1.
- [Nightly build](https://github.com/BrickSchema/Brick/releases/download/nightly/Brick.ttl): Rolling build of master. Use Brick+imports.ttl for end applications, Brick.ttl for platforms.
- [Releases](https://github.com/BrickSchema/Brick/releases): Every release ships a generated list of added and removed classes.
- [Validation shapes](https://github.com/BrickSchema/Brick/blob/master/validation.ttl): The SHACL shapes a Brick model is validated against.

Core structure: eight root classes under brick:Entity — Point, Equipment, Location, Collection,
Measurable, Tag, EntityPropertyValue, Class. Core relationships are paired inverses:
hasPoint/isPointOf, hasPart/isPartOf, feeds/isFedBy, hasLocation/isLocationOf, meters/isMeteredBy,
plus hasTag, hasUnit (QUDT), hasInputSubstance/hasOutputSubstance and isReplacedBy.

## Software

- [brickschema (PyPI)](https://pypi.org/project/brickschema/): First-party Python library — graph loading, OWL-RL/RDFS/SHACL inference, validation, tag inference, BACnet and Haystack ingestion. v0.7.9, published 2025-11-23. `pip install brickschema`
- [Library reference](https://brickschema.readthedocs.io/): API documentation for the Python package.
- [brickify CLI](https://github.com/BrickSchema/py-brickschema): Converts existing metadata (rac, table, rdf, haystack-v4; xls/csv/tsv/RDF inputs) into a Brick model. `pip install brickschema[brickify]`
- [brick_validate CLI](https://github.com/BrickSchema/py-brickschema): Validates a Brick model against the Brick SHACL shapes, pyshacl-style.
- [Brick Example Server](https://github.com/BrickSchema/brick-example-server): Self-hostable HTTP API demonstrating how a Brick model can be abstracted by an HTTP API. OpenAPI 3.0.2, 19 operations under /brickapi/v1/, bearer (JWT) auth.
- [Software interfaces](https://docs.brickschema.org/software/interfaces.html): The documented tooling landscape, including Mortar.

## HTTP surface (self-hosted only)

The Brick Example Server is software you run; there is no hosted base URL. Its nineteen operations
cover timeseries read/write/delete, entity upload (Turtle) and lookup, a relationship-filtered entity
list keyed on the Brick object properties, raw timeseries and raw SPARQL query, actuation, Grafana
dashboard provisioning, and app-token issue/revoke. Only 422 (FastAPI HTTPValidationError) is
documented as an error; there is no pagination, no idempotency, no rate-limit signalling and no
reversal operation for actuation.

## Community and governance

- [GitHub organisation](https://github.com/BrickSchema): Ontology, Python package, documentation, example server, connectors.
- [Issue tracker](https://github.com/BrickSchema/Brick/issues)
- [Contribution guide](https://github.com/BrickSchema/Brick/blob/master/CONTRIBUTING.md)
- [Mailing list](https://groups.google.com/g/brickschema)
- [Brick Consortium](https://brickschema.org/consortium/): The organisational membership body behind the standard.
- [Working groups](https://brickschema.org/working-groups/)
- [Contact](https://brickschema.org/contact/)
- [Brick 2.0 drafting](https://github.com/BrickSchema/Brick2-specification-drafting): Where proposals for the next major line are collected.

## Related standards

Brick declares alignments and shared vocabularies inside the ontology graph itself: ASHRAE 223P
(s223), RealEstateCore (rec, vendored into the distribution), W3C LBD BOT, VBIS, Project Haystack
(adopted terms and a brickify input type), ASHRAE 135 BACnet (external references), QUDT (units), SOSA
and SKOS.

## Known dead links

- https://reconciliation.brickschema.org/reconcile — the hosted reconciliation service the
  BrickSchema/reconciliation-api README still tells OpenRefine users to use. Its TLS certificate has
  expired and the path returns 404 (probed 2026-09-04).
- http://roadmap.brickschema.org/ — redirects to a GitHub org project that returns 404 to
  unauthenticated clients (probed 2026-09-04).