What Key Building Information is
Key Building Information (KBI) is prescribed information about an England higher-risk building that the Principal Accountable Person must give to the Building Safety Regulator. SI 2023/396 regulation 2 defines KBI as the information set out in regulations 3 to 18 — sixteen categories, not a free-text summary.
KBI is the regulator’s structured snapshot of the building: use, envelope, structure, evacuation strategy, and fire/smoke control equipment. Incomplete or stale categories create avoidable compliance risk at registration and every time the building changes.
All 16 categories (regs 3–18)
Plain-English summaries of each prescribed category. Always verify wording against the statutory instrument on legislation.gov.uk.
| Reg | Category | What it covers |
|---|---|---|
| reg.3 | Ancillary building | Whether there is an ancillary building, and whether that ancillary building is itself a higher-risk building. |
| reg.4 | Principal use | Principal use of the HRB and related structures (including ancillary buildings, outbuildings, storeys below ground, and certain temporary buildings incidental to enjoyment of the HRB). |
| reg.5 | Subordinate use | Any subordinate use of the higher-risk building and related structures where subordinate use applies. |
| reg.6 | Change to principal use | Whether, since construction, there has been a change to the principal use of the higher-risk building. |
| reg.7 | Use categories (Approved Document B) | Use must be described using prescribed categories aligned with Approved Document B Table 0.1 — e.g. residential (dwellings), residential (institutional), office, shop and commercial, assembly and recreation, industrial, storage and other non-residential. |
| reg.8 | External wall materials | Materials of the external walls — the building’s envelope description the regulator expects in structured form. |
| reg.9 | External wall insulation | Whether there is insulation of the external wall, and related prescribed particulars. |
| reg.10 | Roof | Prescribed information about the roof of the higher-risk building (materials and related particulars). |
| reg.11 | Fixtures on external wall or roof | Fixtures on the external wall or roof that form part of the prescribed KBI record. |
| reg.12 | Structure | Structural description of the higher-risk building as prescribed for Key Building Information. |
| reg.13 | Storeys below ground | The number of storeys below ground level that are in the higher-risk building. |
| reg.14 | Staircases | Number of staircases, and how many serve (as part of the same flight) the ground storey and every storey above it. |
| reg.15 | Energy supply | The type of energy supply of the higher-risk building. |
| reg.16 | Energy storage | The type of energy storage system of the higher-risk building. |
| reg.17 | Evacuation strategy | A description of the type of evacuation strategy in place for the higher-risk building. |
| reg.18 | Fire and smoke control equipment | A list of fire and smoke control equipment within the building (excluding equipment provided by a resident for their own use) and where it is located. |
The 28-day submission window
After registration, duty-holders have a defined window to submit KBI electronically in the form required by the regulator (see SI 2023/396 submission duties, including the 28-day expectation tied to registration). Track the deadline in the same system as registration and the safety case so categories are not chased in email threads.
- Named owner for each of the 16 categories
- Completion indicators before submit
- Evidence linked into the golden thread
- Deadline visibility for the AP / BSM team
Keeping KBI current
KBI is not a one-time form. When building information changes materially — use, envelope, staircases, evacuation strategy, fire and smoke control equipment — Accountable Persons need a controlled process to update categories, evidence, and related safety-case assertions, and to notify the BSR where registration rules require it (including material-change timescales under the registration regime).
Shorter KBI blog companionHow KBI relates to BAC and the safety case
KBI and Building Assessment Certificates are related but distinct. KBI is submitted around registration under SI 2023/396. A BAC is a later, separate BSR assessment when the regulator directs the PAP. The safety case (SI 2023/907) is the living risk-management narrative — it should stay coherent with KBI facts about use, structure, and fire systems.
How Threadsovereign covers KBI
Every paid plan includes all 16 SI 2023/396 categories with completion indicators, deadline tracking, and structured export packages ready for the BSR portal. Official filing remains on GOV.UK — the platform prepares and evidences; it does not replace the regulator’s portal.
Product walkthrough: Accountable Person software.
Primary sources
- SI 2023/396 — Higher-Risk Buildings (Key Building Information etc.) (England) Regulations (opens in a new tab)
- SI 2023/396 regs 3–18 — prescribed Key Building Information (opens in a new tab)
- GOV.UK — Register or manage a high-rise residential building (opens in a new tab)
- GOV.UK — Preparing a safety case report (updated 6 Dec 2024) (opens in a new tab)
FAQ
Cochise Derrick
Founder & Director
Cochise Derrick is the founder and director of Threadsovereign Ltd and the sole architect and developer of the Threadsovereign platform. With a background as a lead developer on central government digital services and current SC clearance, he brings the technical depth and regulatory understanding required to build compliance infrastructure that duty-holders can genuinely rely on. Threadsovereign is the result of over a year of focused development against the Building Safety Act 2022 and its statutory instruments.
Areas of focus
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Statutory workflows sit on every paid plan. Prepare and evidence in-platform; file on the official BSR portal.