Status codes: why the complexity?

Amodal managing director Thomas Whiting reviews the complexity of status codes following the move to ISO 19650.

To put change into motion, as an industry we have to start opening-up areas of conversation that will alter the way we think collectively. There is plenty of debate within the digital construction sector as to the definition and role of status codes. Generally speaking, these codes define the suitability of information within a document on a common data environment (CDE) and highlight the purpose of important pieces of information at each stage of the design and construction phases. Even though they are clear signposts to denote a document’s context, their simple use is routinely overcomplicated. Why is this the case and what can be done to override any ambiguities?

Corresponding with the RIBA stages, status codes are used by all members of the supply chain to make information traceable and represent project processes. Part of the international BIM standard, ISO 19650, there are specific status codes for a document’s purpose, meaning that these codes change as a project progresses into another period. Statuses S0-S4 are generally used by architects, structural engineers and consultants who are involved in the design stage of a building project. The latter stages, S4 and up, are typically employed during the sign-off phases at the end of stages, and pave the way for construction.

Status codes let stakeholders share information that isn’t ready for the authorisation stage, yet needs to be communicated to the relevant parties to ensure greater collaboration between those involved in the design stages. Status codes provide important clarity as to the purpose of a document; they highlight whether a document is specifically for comment, for instance. They also act as a signpost to prevent any confusion and project delays, which is beneficial to construction supply chains at large.

As the standards are for guidance purposes, some stakeholders use “T” for ‘tender’, which may seem logical but isn’t in the standards, meaning it just leads to inconsistency.– Thomas Whiting, Amodal

Where the complications arise

Even though status codes play an important role in highlighting the development of a piece of building information, their use is often misunderstood in many ways for few reasons.

One of the areas causing some confusion is in terms of the standards, which have recently changed. Companies used to work to the BS 1192-1 suite, yet this has now been amalgamated into the ISO 19650 standards. While this transition will enable businesses from all around the world to speak a common language, the shift has inevitably created complications that could have been avoided if any pertinent changes from one standard to another were indicated. For instance, there used to be status codes that began with ‘D’: D4 represented the issue for tender stage; in the ISO standard this letter has been omitted yet, as we are creatures of habit, people are still using them. As the standards are for guidance purposes, some stakeholders use “T” for ‘tender’, which may seem logical but isn’t in the standards, meaning it just leads to inconsistency.

Further confusion can be compounded by stakeholders who misinterpret revision types. These are designed to sit next to status codes and highlight which stage of revision the document is at. The revision typically has a prefix, either a ‘P’ or ‘C’ – preliminary and contractual – although some stakeholders falsely interpret the ‘C’ as ‘construction’. Clearly, there is a demand for greater governance of or long-term assistance for companies who are not quite meeting the standard and, whether they are aware of it or not, are causing the ambiguity that ripples throughout project supply chains.

Do the standards need refining?

By educating workforces and ensuring the mechanisms are in place to manage the use of status codes, errors will gradually disappear. But before that happens, there does need to be greater clarity regarding a few of the updates that have been made to the ISO standards.

The ISO 19650 standards have removed the D1-D4 codes and introduced the S5 code. This leaves the question for users and organisations that were using these codes – what should they do now? What was a consistent approach has now led to inconsistency. S5 has also been added to mean ‘withdrawn’ and should have no revision associated with it. CDEs are designed so information cannot be removed, yet how should the industry interoperate this? People will develop different solutions depending on their process and the capability of the CDE, which isn’t ideal. It is now 13 years since BS1192-1 was produced, which begs the questions: are we learning our lessons or is the industry too slow to change? 

Although status codes have the potential to play an important part in enabling efficiencies across construction projects, their value is not being realised at present. In the construction industry there are all manner of labels and signs to indicate how a product should be installed or whether something is a risk. Why isn’t the sector, then, making use of a process that can highlight what a document is for and whether a drawing is the right version they should be using? While the change in standards has resulted in shortfalls, with the right behaviour change and governance, there will be little reason as to why status codes cannot be utilised effectively in a very near future.

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  1. S5 never meant ‘withdrawn’ : the standard said ‘(withdrawn)’ which is perfectly informative. Long ago S5 was withdrawn as its meaning, now long forgotten, was not useful.

  2. I’m not sure ISO 19650 “introduced the S5 code”. The national annex was based on 1192 that withdrew the S5 code in the 2010 issue. Nothing to do with withdrawn documents. Just issue the next revision with a big “WITHDRAWN” stamp across the document to keep the CDE up-to-date.

    Using “C” in line with the standards doesn’t add any value for what I do. Whatever the revision is when it is made contractual is the contractual revision. People understand P for preliminary, C for Construction. Again no need for T as a P revision document will be referenced in the tender pack to tender against.

  3. Hi Thomas,

    I think you have to consider is a standards are design for voluntary use and you’re not forced to follow a set of rules. Which you mention “As the standards are for guidance purposes, some stakeholders use “T” for ‘tender’, which may seem logical but isn’t in the standards, meaning it just leads to inconsistency”. Anyone can request you follow a standard or not. Some organisations can’t use the naming containers outlined in ISO 19650 and request you follow their specific naming containers and status codes.

    Personally I think as long as it is clearly documented what is required it should not matter what is used as long as the whole project team use the same.

  4. Good to see the comments are only further highlighting the confusion.

    Yes the standards are for guidance purposes so deviations will occur to suit client requirements, but the core standard should be clear for people to understand and not result in different processes.

    This is clearly not the case, I only hope when the standard is updated things become clearer for the industry to use.

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