What is IDS? A Plain-English Guide to the buildingSMART Standard

IDS (Information Delivery Specification) is how you define what data must be in an IFC model. Here is what it is, why clients use it, and how to make one from Excel.

Every BIM project has data requirements. The client wants fire ratings on walls. The facility manager wants manufacturer names on every pump. The cost consultant wants Uniclass codes on everything. Historically, those requirements lived in PDFs that nobody could check automatically. IDS is how the industry finally fixed that.

IDS stands for Information Delivery Specification. It is a buildingSMART standard — the same organisation that maintains IFC itself — for describing model data requirements in a machine-readable file. If IFC is the common language for the geometry and data, IDS is the contract that says "here is what data must be present in that file." Published as a finalised standard in 2024, IDS is rapidly becoming the default way of specifying BIM deliverables on public and increasingly private projects.

What a single IDS rule looks like

An IDS rule has two halves:

  • Applicability. Which elements does the rule apply to? "All IfcWall instances on external storeys."
  • Requirement. What must those elements have? "A FireRating property in Pset_WallCommon with a value of at least 60 minutes."

Multiply that pattern across fifty or a hundred rules and you have a complete project data specification that a validator can run automatically against any IFC file.

Why IDS matters more than a PDF specification

  • Checkable. A tool reads the IDS and produces a pass/fail report. No human has to read each wall property one by one.
  • Contractual. The IDS becomes part of the deliverable contract. The client does not have to argue over whether requirements were met.
  • Versioned. Requirements evolve. IDS files live in version control alongside the project, with clean diffs between revisions.
  • Portable. Every compliant validator — commercial and free — reads the same IDS file. No vendor lock-in.
  • Automatable. Run validation in your CI pipeline, on every file upload, or as a pre-submission check.

How to make an IDS file

You have three options, in increasing order of power:

  1. Spreadsheet-first. If your requirements already exist in Excel — a typical BIM Execution Plan or Employer's Information Requirements document — you can fill in BIMCamel's CSV template and import it. One row per rule. See the dedicated guide How to Create an IDS File from Excel for Free.
  2. Visual editor. Open IDS Maker in BIMCamel. Add specifications one by one with a form-based editor. Each specification has applicability (IFC class, predefined type, attributes) and requirement facets (property, classification, material, attribute). Preview the XML and download a valid .ids file.
  3. Hand-edit XML. IDS is an XML format. If you are comfortable editing XML, you can write IDS files in any text editor. Most people do not need this — the visual editor covers every feature.

How to use an IDS file

Once you have a .ids file:

  1. Upload the IFC model you want to check.
  2. Open Validate Model.
  3. Upload the IDS file or select one from your library.
  4. Click Run. BIMCamel walks every element and tests every rule.
  5. Read the report. It shows every specification with a pass count, fail count, and the GUIDs of failing elements.
  6. Fix failing elements in the authoring tool, re-export, re-validate.

What kinds of rules IDS supports

  • Property checks — "must have FireRating property," "must have manufacturer name."
  • Property value checks — "FireRating must be at least 60 minutes," "IsExternal must be true for external walls."
  • Classification checks — "must have a Uniclass 2015 code," "must have an OmniClass code."
  • Attribute checks — "Name attribute must match a regex pattern."
  • Material checks — "structural elements must have a Material assignment."
  • Entity checks — "the file must contain at least one IfcSite entity."

Typical use cases

  • Client-side compliance. A client publishes an IDS with their EIR. Every file delivered to them is auto-validated before acceptance.
  • Internal QA. Your own firm publishes an IDS for minimum model quality. Every outgoing deliverable is validated first.
  • Phase gates. Different IDS files for concept, tender, and as-built stages. The right rules check at the right time.
  • Facility management handover. The FM team publishes an IDS defining exactly which asset data they need.

If you work on any project with a formal BIM mandate, IDS is no longer optional. BIMCamel's IDS Maker and Validate Model tools together let you produce and enforce a spec without buying any commercial validator.

Tools mentioned in this guide

Part of BIMCamel's Learn library — browse the free online tools or see every guide.