“IDS validation” can refer to two different tasks: checking that an IDS file is valid, and checking whether an IFC model satisfies the requirements in that file. Keep those tasks distinct when planning a delivery review. buildingSMART's explanation of auditing and checking
What does an IDS audit check?
An IDS audit examines the specification file. buildingSMART's IDS Audit Tool supports quality assurance of IDS files and includes checks associated with the IDS schema and IFC-related definitions. The precise checks depend on the tool version. IDS Audit Tool documentation
For your project, record the tool and version used, review its feedback and correct problems in the file before issuing it. Passing an audit is useful evidence about the file, but you should still check that the specification expresses the requirement you intended.
What does IFC checking against IDS do?
An IDS-capable model checker evaluates the IFC delivery against the supplied specifications and reports results. For example, IfcTester supports checking IFC models against IDS and producing reports. IfcTester documentation
Plan the review around three questions: was the intended model checked, was the intended IDS release used, and did the specifications select the intended objects?
A practical way to test a specification
Prepare a small sample in which the expected outcome is known in advance. Include an object that should satisfy the requirement, an object with the requested information missing, and an object that should fall outside the specification's scope.
For a hypothetical rule requiring an agreed project property on walls, write the expectations before checking:
| Sample object | Expected treatment |
|---|---|
| Wall with the agreed property and an allowed value | Should satisfy this rule |
| Wall without the required property | Should fail this rule |
| Door outside the wall specification | Should not be assessed by this rule |
Review more than the headline result
Check the number and identity of applicable objects. If the model contains the walls you expected but the specification selects none, investigate the selection logic. A result without that context can be misleading.
When a rule fails, inspect the exported IFC information before assigning a correction. The source model, export mapping, specification or scope might need attention. Record the decision so that the next delivery is checked against an understood requirement.
Keep a reproducible review record
Retain the model issue, IDS release, checker/version and resulting report together in the project's agreed record system. When a requirement changes, identify the changed release before running another comparison.
That record makes it easier to explain a result later and to distinguish an information correction from a change in the requirement itself.
Read the guide to applicability and requirements, explore IDS examples, or prepare your specifications in IDS Compass.