Gateway 2 is the approval a higher-risk building needs before construction can start. Here is what the application must contain, and where firestopping evidence fits.
Checked against BSR guidance on 21 July 2026. Written by a BM TRADA Q-Mark certified firestopping installer.
Gateway 2 is the building control approval stage for a higher-risk building. It is a hard stop before construction can begin, at which the Building Safety Regulator checks that the design meets the Building Regulations. Approval has to be granted before work starts.
The gateways apply to higher-risk buildings. In law that means a building at least 18 metres tall, or with at least 7 storeys, whichever is reached first, containing at least two residential units. In the design and construction phase the same height test also captures hospitals and care homes. A building below that threshold is not higher-risk and does not pass through the gateways, though other fire-safety duties still apply to it.
There are three gateways. Gateway 1 sits at planning. Gateway 2 is the pre-construction approval covered by this page. Gateway 3 is the completion stage, before the building can be occupied. The Building Safety Regulator, which since 27 January 2026 has been an independent body sponsored by the Ministry of Housing, Communities and Local Government, assesses each one.
The client applies to the Building Safety Regulator with a set of documents that demonstrate how the design will comply with the Building Regulations. The core of it is a fixed list.
Checked against BSR guidance on 21 July 2026. This list follows the current GOV.UK guidance on preparing a building control approval application. The regime is still moving, though. Treat this page as a plain-English orientation, and confirm the requirement for your own project before you submit.
Primary source: GOV.UK, “Preparing information for a building control approval application.”
The single most common confusion is treating installed-work evidence as a Gateway 2 input. It is not. Gateway 2 approves the design before work starts. The record of what was actually built belongs to the golden thread and Gateway 3.
Design stage. Approval required before work starts.
Build stage onward. Handed over at completion.
A firestopping contractor does not submit anything to the Building Safety Regulator. The client and principal contractor hold the duty and make the submission. What a specialist supplies is the evidence that goes into their documents: at Gateway 2, the design-stage confirmation that the compartmentation strategy is deliverable with tested systems; through construction, the installation record that supports the golden thread.
That is the practical value of certified installation. Skyline's firestopping is third-party certified to the BM TRADA Q-Mark, and every penetration, joint and cavity is photographed before cover-up, tagged and captured as the work goes in rather than reconstructed afterwards. When an RFI, a stop notice or a Gateway query asks the dutyholder to prove a seal, the answer is already recorded.
Not as a single named document the regulator asks for. A Gateway 2 application is a defined set of documents. It includes drawings, a fire strategy, control plans and a competence declaration, among others. Firestopping evidence supports the fire-safety case within those documents; it is not a standalone pack submitted on its own.
A building at least 18 metres tall or with at least 7 storeys, whichever comes first, containing at least two residential units. During design and construction the height test also captures hospitals and care homes. Buildings below that threshold do not pass through the gateways.
The client, as the dutyholder, applies to the Building Safety Regulator, supported by the principal designer and principal contractor. A firestopping subcontractor does not submit to the regulator; it supplies evidence into the dutyholder's documents.
Not usually. Gateway 2 approves the design before construction. Installation records and as-built photographs belong to the golden thread and are handed over at Gateway 3, the completion stage. At Gateway 2 the firestopping question is about the strategy and the tested systems named in the design.
The Building Safety Regulator can request further information or reject the application, and construction cannot start until approval is granted. A well-evidenced fire-safety case, with the compartmentation strategy shown to be deliverable, is part of avoiding that delay.
It was checked against Building Safety Regulator and GOV.UK guidance on 21 July 2026. The regime is still settling — the regulator became an independent body in January 2026 — so confirm the current requirement for your specific project before you rely on any list.
The free field guide shows what a defensible golden-thread evidence trail looks like, and where firestopping evidence usually falls short before a gateway or an audit asks for it.
BM TRADA Q-Mark certified firestopping installer. Our work is behind the walls of The Gherkin, Olympic Park and Grosvenor Square. Greater London and the M4 corridor.