If you're working on any building over 18 metres or seven storeys in England, you now have a legal obligation to maintain a Golden Thread of Information. Most small structural engineering firms doing this work don't have one. Not because they're ignoring the law. Because nobody has clearly explained what 'a digital record of building information, maintained throughout the building's lifecycle and accessible to all relevant parties on demand' actually requires from a 5-person practice.
The answer is more specific, and more achievable, than most guidance suggests.
What the Golden Thread actually is
The Golden Thread of Information is a requirement introduced by the Building Safety Act 2022, following the recommendations of Dame Judith Hackitt's Building a Safer Future report in 2018. It applies to Higher-Risk Buildings in England: buildings at least 18 metres tall or with at least 7 storeys, containing at least 2 residential units.
The core requirement is this: a digital record of all relevant building information must be created and maintained throughout design, construction, and occupation. It must be retrievable on demand and handed over at each gateway stage. It includes structural information, fire safety information, building control approvals, changes to the original design, and dutyholder sign-offs.
For structural engineers, this means your structural calculations, revised drawings, building control correspondence, and gateway submissions are all part of the Golden Thread. Under the Building Safety Regulator's guidance, these must be in a retrievable digital format and handed over to the Principal Accountable Person on completion.
What you are actually required to store
For the design and construction phase, the Golden Thread documentation a structural engineering firm must maintain includes: initial structural design calculations with version history, all revised drawings with the reason for revision recorded, building control submissions and approvals, communications that led to significant design changes, CDM documentation including the pre-construction information and construction phase plan, and any structural assessments carried out during construction.
The version history element is where most firms' current systems fail immediately. Dropbox does not maintain a reliable version history of who changed what and why. A folder of PDFs named 'revised_drawing_FINAL_v3' is not a Golden Thread. An auditable project record where every document, every version, and every piece of correspondence is timestamped and linked to the project is.
The Principal Designer's specific responsibility
Under the Building Safety Act, the Principal Designer is responsible for coordinating the Golden Thread during the design phase and ensuring it is handed over in a compliant format at gateway submissions. This is distinct from the CDM Principal Designer role, though in practice the same firm often holds both appointments.
The BSR's guidance is specific: the Principal Designer must be able to demonstrate, on request, that the information exists and is complete. For a small structural engineering firm acting as Principal Designer on an HRB project, that's not an abstract compliance concept. It's a document request you need to be able to answer within hours.
The consequences of not being able to produce the Golden Thread are significant. The Building Safety Regulator's enforcement strategy includes stop notices, improvement notices, and prosecution for dutyholders who cannot demonstrate compliance. At the revenue level most small practices operate, a single enforcement action is not a financial inconvenience. It's an existential event.
The practical system requirement
What the Golden Thread requires from a technology standpoint is a project record that holds all documents with version history, all relevant correspondence in context, all approvals and sign-offs linked to the relevant documents, and a way to export or share that record as a complete, auditable package.
Most firms running Excel, Outlook, and Dropbox cannot produce this reliably. The documents are in Dropbox. The correspondence is in Outlook. The approvals are in PDF attachments. There is no way to present the complete project record as a coherent, auditable whole.
One Uncle's project record holds every email, calculation, drawing, approval, and note attached to a project in one place. Version history is maintained automatically. The record can be accessed by any authorised team member. For structural engineers working on Higher-Risk Buildings, this is a compliance requirement with a legal obligation attached, not a feature choice.
If you're not working on HRBs yet
The Golden Thread currently applies to Higher-Risk Buildings. But the direction of regulation is clear. The BSR's published enforcement priorities have signalled that documentation standards will extend beyond HRBs over time. And even for residential projects below the 18-metre threshold, the Building Safety Act has raised the practical expectation for what structural documentation should look like.
A project record system that works for Golden Thread compliance works for everything else. The discipline of maintaining complete, auditable project documentation isn't a regulatory burden specific to tall buildings. It's how every structural engineering project should be documented. Regulators have made it mandatory for the most complex projects first. The others are next.
