An Information Delivery Manual (IDM) describes one information exchange in a project process in plain terms: which parties are involved, what triggers the exchange, what information is handed over and what the receiver does with it. The method is published as ISO 29481 and is maintained by buildingSMART International. An IDM says nothing yet about file formats; it is the business view that later becomes a technical one (an MVD or an IDS).
At a glance
| Published as | ISO 29481 (part 1 methodology, part 2 interaction framework, part 3 data schema) |
| Answers | Who gives what to whom, at which moment, for what purpose |
| Written by | Domain experts with information managers |
| Leads to | An MVD or an IDS that software can implement or check |
| Typical length | A process map plus a few pages of exchange requirements |
The parts
- Process map: the activities of each party in swimlanes, with the points where information crosses from one lane to another.
- Exchange requirements: for each crossing, the information needed, described in the language of the discipline (for example "space name, net area, fire compartment").
- Use cases: the purpose of the exchange, such as energy analysis or quantity take-off for a cost plan.
- Business rules: conditions the information must meet, such as "every space belongs to exactly one storey".
How it is used on projects
Few project teams write a full IDM. The idea is used more often than the document: an information requirement that names the exchange, the parties, the milestone and the purpose is an IDM in miniature. Industry groups and software vendors write complete IDMs for common exchanges (structural analysis, energy, handover) so that the same requirement can be reused across projects.
Variations
- Formal IDMs follow ISO 29481 closely and are published by buildingSMART chapters or industry bodies.
- Light IDMs are a single table per exchange in an EIR or BEP: from, to, when, what, why.
- Newer work links exchange requirements directly to IDS files, so the requirement can be checked by software the day it is written.
Common misunderstandings
- "An IDM is a file format." It is a description of a process and its information; the format comes later.
- "IFC makes IDMs unnecessary." IFC can carry almost anything; the IDM says which part of it matters for this exchange.
- "Only software developers need IDMs." The questions an IDM asks are the questions every EIR should answer.
Where to read more
ISO 29481-1 and ISO 29481-2 for the method; buildingSMART International's pages on IDM and its published use cases; the lessons on information requirements and the IDS entry for the machine-readable end of the chain.