Official definition of golden thread approved

London high-rise buildings (Image: Dreamstime/Luke Sanderson)

The Ministry of Housing, Communities and Local Government (MHCLG) has approved a formal definition of the golden thread, following consultation with the HSE, fire safety engineers, construction firms and other stakeholders.

The definition and principles were drafted by the Building Regulations Advisory Committee’s (BRAC) Golden Thread Working Group and have recently received ministerial approval, according to BIM+. Following the lifting of an embargo, the definition has been shared online by the BIM4 Housing Associations (BIM4HAs) initiative.

The definition sets out five key criteria, backed by a nine-point annex. In summary, the golden thread covers the information, documents and information management processes used to support building safety.

Information is defined as “all the information necessary to understand and manage risks to prevent or reduce the severity of the consequences of fire spread, or structural collapse in a building”.

Building safety is not limited to the building itself, but also incorporates “all the people in or in the vicinity of a building”, including emergency responders.

The annex highlights that information could be held in a common data environment, but that there is no requirement for such.

As a ‘single point of truth’, the golden thread “will record changes, including the reason for change, evaluation of change, date of change and the decision-making process” and who made the changes.

Information will need to be held in a “structured way” and will “likely align with the rules around open-source data – so that information can be handed over in the future and still be accessed”.

The final point of the annex emphasises that the golden thread should be regularly reviewed for the relevance of information to building safety and that “if information is no longer relevant to building safety, it does not need to be kept”.

How the definition was drafted

Jack Ostrofsky, BIM4HAs chair and head of quality and design at Southern Housing Group, sat on the BRAC Working Group. He told BIM+ about the process that the BRAC working group went through: “There were more than 40 people in the working group – including the likes of the Health and Safety Executive, fire safety engineers, housing associations, architects, contractors, specialists and industry stakeholder bodies

“There was a lot of constructive discussion. There were several drafts that were circulated. I think it was a smooth evolution in clarification. It’s a product of industry and has been through a rigorous approval. It is carefully crafted in order to enable industry to respond [to its requirements] and to be workable.”

He noted that the definition does not mandate a BIM process or adherence to ISO 19650, but “speaking for BIM4HAs and Southern Housing, we are absolutely confident that applying 19650 is one of and probably the best way to meet the golden thread obligations”.

The definition will be included in the Building Safety Bill when it is laid before Parliament, but Ostrofsky voiced a shared concern that the finer detail of the definition could be lost among all other elements of the Bill and hence the importance of industry professionals reviewing it now.

He added: “The legislation has to be debated in Parliament, it will be consulted on, so [this current approved] definition might change at that point.”

Golden thread: full definition
  • The golden thread will hold the information that those responsible for the building require to identify, understand, manage and mitigate building safety risks in order to prevent or reduce the severity of the consequences of fire spread, or structural collapse throughout the lifecycle of the building. The information stored in the golden thread will be reviewed and managed so that the information retained at all times achieves this purpose.
  • The golden thread covers both the information and documents, and the information management processes (or steps) used to support building safety. The government has defined the information as including all the information necessary to understand and manage risks to prevent or reduce the severity of the consequences of fire spread, or structural collapse in a building.
  • The golden thread information should be stored as structured digital information. It will be stored, managed, maintained and retained in line with the golden thread principles (see annex below). The government will specify digital standards, which will provide guidance on how the principles can be met.
  • The digital thread information management approach will apply through design construction, occupation, refurbishment and on-going management of buildings. It supports the wider changes in the regime to promote a culture of building safety.
  • Building safety should be taken to include the fire and structural safety of a building and the safety of all the people in or in the vicinity of a building, (including emergency responders).

Annex: draft golden thread principles
  • Accurate and trusted: the duty holder/accountable person/building safety managers and other relevant persons (eg contractors) must be able to use the golden thread to maintain and manage building safety. The regulator should also be able to use this information as part of their work to assess the safety of the building and the operators safety case report, including supportive evidence and to hold people to account. The golden thread will be a source of evidence to show how building safety risks are understood and how they are being managed on an on-going basis. Thread must be accurate and trusted. It will not be used unless people trust that the information in the golden thread is accurate and up to date. The information produced will therefore have to be accurate, structured and verified, requiring a clear change control process that sets out how and when information is updated and who should update and check the information.
  • Residents feeling secure in their homes: residents will be provided information from the golden thread – so that they have accurate and trusted information about their home. This will also support residents in holding accountable persons and building safety managers to account for building safety. A properly maintained golden thread should support accountable persons in providing residents the assurance that their building is being managed safely.
  • Culture change: the golden thread will support culture change within the industry, as it will require increased competence and capability, different working practices, updated processes and a focus on information management and control. The golden thread should be considered an enabler for better and more collaborative working.
  • Single point of truth: a golden thread will bring all information together in a single place (potentially a common data environment), meaning there is always a single point of truth. It will record changes (ie updates to information/plans), including the reason for change, evaluation of change, date of change and the decision-making process. This will reduce the duplication of information (email updates and multiple documents) and help drive improved accountability, responsibility and a new working culture.
  • Secure: the golden thread must be secure with sufficient protocols in place to protect personal information and control access to maintain the security of the building or residence. It should also comply with current GDPR legislation where required.
  • Accountable: the golden thread will record changes (ie updates to information), when these changes were made, and by who. This will help drive improved accountability. The new regime is setting out clear duties for the duty holders and the accountable person for maintaining the golden thread information to meet the required standards. Therefore there is accountability at every level, from the client/accountable person to those designing, building or maintaining a building. This will mean that changes can more easily be tracked. And this will support better building safety.
  • Understandable/simple to access (accessible)/consistent: the golden thread needs to support the user in their task of managing building safety. The information in the golden thread must be clear, understandable and focused on the needs of the user. It should be presented in a way that can be understood and used by users. This also should consider that users have different needs. The information should be accessible so that people can easily find the right information at the right time. This means that the information needs to be stored in a structured way (ie like a library), so people can easily find, update and extract the right information. The government will set out the digital standards which will apply to the golden thread. Storing information to digital standards would mean the information is stored in a structured way. To support this dutyholders/accountable person should where possible, make sure the golden thread uses standard methods, processes and consistent terminology so that those working with multiple buildings can more easily access, understand and use the information consistently and effectively.
  • Longevity/durability of information: the golden thread information needs to be formatted in a way that can be easily handed over and maintained over the entire lifetime of a building. In practical terms, this is likely to mean that it needs to align with the rules around open source data – so that information can be handed over in the future and still be accessed. Information should be able to be shared and accessed by contractors who use different software. And if the building is sold, the golden thread information must be accessible to the new owner. This does not mean everything about a building and its history needs to be kept. The golden thread must be reviewed to ensure that the information within it is still relevant and useful.
  • Relevant/proportionate: preserving the golden thread does not mean everything about a building and its history needs to be kept and updated from inception to disposal. The objective of the golden thread is building safety and therefore if information is no longer relevant to building safety, it does not need to be kept. The golden thread, the changes to it and processes related to it must be reviewed periodically to ensure that the information comprising it remains relevant and useful.

Ostrofsky concluded: "I would strongly encourage anyone in the residential built environment sector to take the time to digest this and think about how to put it to use straight away."

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  1. As a ‘single point of truth’, the golden thread “will record changes, including the reason for change, evaluation of change, date of change and the decision-making process” and who made the changes.

    This sounds good for the definition, but here is a question on how to interpret and implement this.

    Change or Design development?
    They are not the same thing.

    In the design development process there are many individuals involved. Please don’t overlook the role of the Design Manager here as the person who pulls these people together.
    Almost every project includes some element of design development – even if it is a standard building contract with bills of quantities, there will be some packages of work where the design has not been developed at the time of the contract award. So arguably some design development – even for straight forward decisions on depth of foundation or design mix of concrete – may not be deemed as change.
    The Design Manager (DM) chairs the DTMs and minutes them. Decisions are taken at these meetings to proceed down one route or another for design development – and under the direction of the DM the specialist contractors, suppliers and design consultants feed each other with the information needed for designs to be developed.
    The DM also controls the drawing progression and checking process of the respective designs in conjunction with the lead consultant, the PM and the QS before designs are approved as construction-ready. This is the evaluation bit.

    But that was the life of a Design Manager when everything was managed on a CDE. How does it work now?
    Are the DTM minutes part of the single point of truth? The minutes may be where substitution of materials first gets recorded as an option in the design development discussions. Now with material shortages, the PM and the QS will be demanding substitution even more.

    Are all the comments and last minute requests made by those in the checking process part of the single point of truth? Some of these comments swing the decisions on design solutions.
    Or is it the final evidence of completed installations – with photos and test results and commissioning certificates – that is ultimately the single point of truth?
    Maybe it is time to recognise the importance of Design Managers for the management of the golden thread of information.

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