The golden thread explained
A working guide to the golden thread under the Building Safety Act: which buildings need one, what the law requires during design, construction and occupation, and how architects should structure the information they produce.
What is the golden thread under the Building Safety Act?
The golden thread is the digital record of information about a higher-risk building that shows how it was designed and built to comply with building regulations, and how it is kept safe once occupied. In England it is a legal requirement: the client must keep it electronically during design and construction, and the accountable person must maintain it for the life of the building.
The concept came from Dame Judith Hackitt's review after the Grenfell Tower fire. The Building Regulations Advisory Committee's golden thread report, published by government on 21 July 2021, defines it as the information that allows someone to understand a building and the steps needed to keep the building and the people in it safe, now and in the future. It covers both the information itself and how it is managed.
In law, the term is used in two places:
- Design and construction
- Regulation 31 of the Building (Higher-Risk Buildings Procedures) (England) Regulations 2023, headed "Golden thread", in force since 1 October 2023.
- Occupation
- Sections 88 and 89 of the Building Safety Act 2022, with content set by the Higher-Risk Buildings (Keeping and Provision of Information etc.) (England) Regulations 2024 and standards set by regulation 7 of the Higher-Risk Buildings (Management of Safety Risks etc) (England) Regulations 2023.
For architects, the golden thread starts with the design. Much of what ends up in it is drawings, specifications, compliance statements and change records that the design team produces, so the way that information is structured from the outset decides whether the thread is usable at handover.
Which buildings need a golden thread?
The legal golden thread applies to higher-risk buildings in England. The definition is slightly wider during design and construction than in occupation, because it includes hospitals and care homes.
Design and construction
At least 18m high or at least 7 storeys, and containing at least two residential units; or a hospital or care home meeting the same height test.
Occupation
At least 18m high or at least 7 storeys, with at least two residential units, under Part 4 of the Act.
The design and construction test comes from section 120D of the Building Act 1984 and the Higher-Risk Buildings (Descriptions and Supplementary Provisions) Regulations 2023.
Other buildings do not have a statutory golden thread. Many clients still ask for one, because the same discipline makes Building Regulations compliance, regulation 38 fire safety information and the CDM health and safety file easier to deliver.
Legal requirements during design and construction
Regulation 31 puts the duty on the client, who can act through someone else. It sets standards for how the information is kept, and a sequence for what goes in and when.
How the information must be kept
- An electronic facility is set up and designers and contractors have access to it.
- Information is held electronically, in a form that can be transferred without loss or corruption.
- It is accurate, up to date and understandable to its intended users, with any keys needed to interpret it.
- It is available promptly when the principal designer or principal contractor asks.
- It is protected from unauthorised access, with a record of who changed what and when.
- Terminology is consistent where practicable.
What goes in, and when
- BEFORE GW2
Design information
Added before the building control approval application to the BSR.
- BEFORE START
Updated design
Design information updated before construction starts.
- ON APPROVAL
Approved set
Fire statement, approved plans and evidence of compliance.
- CONSTRUCTION
Changes and reports
Change control records, revisions, dutyholder changes, occurrence reports.
- COMPLETION
Handover
Completion application and documents; thread passes to the accountable person.
During construction the client also adds documents agreed under approval conditions and notices of changes of principal designer or principal contractor. Earlier versions of updated documents remain part of the golden thread.
At completion, regulation 38 of the same regulations requires the client to hand the golden thread information to the accountable person, keeping the filing structure, indexes and keys, in a format they can read, keep and update. The recipient must confirm in writing that they can access it and that it is sufficient to understand, operate and maintain the building and its fire safety systems. The regulations do not prescribe specific software.
Requirements once the building is occupied
Section 88 of the Building Safety Act 2022, in force since 16 January 2024, requires accountable persons for an occupied higher-risk building to keep prescribed information and documents to prescribed standards, and to keep them up to date.
Schedule 1 to the 2024 Keeping and Provision of Information Regulations lists what must be kept. Section 89 and the 2024 regulations set out who must be given access, including the Building Safety Regulator, residents, other accountable persons, the fire and rescue authority and clients for later building work.
The standards in regulation 7 of the 2023 Management of Safety Risks regulations mirror those during construction: electronic, transferable, accurate, understandable, retrievable promptly, secure, and with changes recorded.
The thread the accountable person inherits is only as good as the structure the design team started with.
The golden thread principles
The Building Regulations Advisory Committee report sets out ten principles. They are not themselves law, but they explain what the regulations are trying to achieve.
- 01
Accurate and trusted
Reflects what was actually designed and built.
- 02
Residents feeling secure
Residents can get the information relevant to their safety.
- 03
Culture change
Part of how the project is run, not an afterthought.
- 04
Single source of truth
One authoritative version, not copies on several servers.
- 05
Secure
Protected against unauthorised access and loss.
- 06
Accountable
Clear record of who added or changed what, and when.
- 07
Understandable
Common terminology and structure so others can use it.
- 08
Accessible
Information can be found and retrieved quickly.
- 09
Durable and shareable
Usable for the life of the building, in open formats.
- 10
Proportionate
Focused on building safety, not every project file.
Several mirror the regulation 31 duties: security, a record of changes, understandable information and prompt access are all written into the law. The others describe how a project team should behave.
How architects should structure golden thread information
The client owns the duty, but the design team creates most of the content. A few habits, set at the start, make a large difference at handover.
- Agree the structure at the start. Agree a folder and naming structure, metadata and terminology with the client and principal designer before Gateway 2 documents are drafted. Retrofitting structure at handover is expensive.
- Link compliance to evidence. The Building Regulations compliance statement for Gateway 2 explains how each element complies. Link each claim to the drawing, specification clause, test report or calculation that proves it.
- Keep a controlled change log. Record every design change with its reason, who approved it and which documents it affected, so the thread shows the as-built position.
- Keep superseded versions. The regulations treat earlier versions as part of the golden thread. Do not overwrite; supersede.
- Separate safety information from project noise. Fire strategy, structure, external wall, compartmentation, fire doors, smoke control and building services all matter. Internal design team emails mostly do not.
- Align with other deliverables. Regulation 38 fire safety information, the CDM health and safety file and the golden thread overlap. Produce the information once and reference it in each.
A thread built this way shows the as-built position and how it was reached, which also makes Gateway 2 and completion applications easier to assemble.
For more on the specification side, see our post on fire safety specifications after the Building Safety Act.
Where Avoice fits
Most golden thread problems are structural: compliance claims with no linked evidence, overwritten revisions and safety information buried in project files.
Avoice's Compliance module includes a Golden Thread view and export that pulls together the Building Regs Tracker, CDM Designer's Risk Register and Planning Conditions tracker into a structure shaped around the Building Safety Act requirements. Every document and decision is logged with its date and author in the Project Record, and the Building Regs Tracker links each requirement to its evidence.
Software can structure, log and export. The client remains responsible for the golden thread, and the design team for the accuracy of what goes into it.
Build the golden thread as you design
A Golden Thread view and export that brings together the Building Regs Tracker, CDM risk register and planning conditions, with every document and decision logged.
This guide is for general education and is not professional advice. Check the current regulations on legislation.gov.uk and the Building Safety Regulator's guidance before relying on any provision.