What Your Specification Must Show at Gateway 2
The specification angle on the Building Safety Regulator's building control approval application for higher-risk buildings
Gateway 2 is decided on documents, and the specification is where the building's products, performance and evidence are written down. The Building Safety Regulator does not list the specification as a standalone upload, but its guidance asks for a compliance statement that explains each element and points to the drawings. A specification that cannot support those claims is a likely cause of delay. This guide covers what the specification has to evidence, how far contractor-designed work must be resolved, and how it behaves once the application is approved.
Each safety-critical element needs a stated performance, a whole system and evidence for the configuration proposed, with a record when any of it changes.
What does the BSR expect, and where does the specification come in?
The BSR expects a compliance statement, fire and emergency file, drawings, construction control plan, change control plan and mandatory occurrence reporting plan, among other documents. The specification supports the claims in several of them, even though it is not a standalone upload.
The existing Avoice guide to Gateway 2 submissions sets out the full document list, the decision periods and the common reasons for rejection. This guide does not repeat it. It takes the specifier's question: which of those documents rely on the specification, and what has to be in it for the claims they make to stand up?
Gateway 2 is the building control approval application that the Building Safety Regulator (BSR) must approve before building work starts on a higher-risk building in England. It comes from the Building Safety Act 2022 and the Building (Higher-Risk Buildings Procedures) (England) Regulations 2023 (SI 2023/909), which came into force on 1 October 2023. The BSR's guidance on preparing the application describes each document the applicant uploads. Several of them lean on the specification, whether or not it is named.
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| Gateway 2 document | What the BSR guidance asks for | What the specification contributes |
|---|---|---|
| Building regulations compliance statement | For each element, how the work meets the functional requirements, the guidance or standards followed, why they were chosen and why they achieve compliance, with reference to the drawings. | The performance, products and standards behind each claim, in terms that match the statement. |
| Fire and emergency file | Plans and strategy for escape and warning, internal and external fire spread, fire service access, and how the design deals with structural failure and fire spread. | The fire-rated constructions, products, classifications and test evidence the strategy depends on. |
| Drawings and plans | Labelled drawings that describe the scope and show compliance, with a reference file listing each one. | Consistent identifiers, performance values and notes, with no second version of a requirement on the drawings. |
| Construction control plan | How compliance will be evidenced during construction, including the expected evidence and who collects it. | The inspection, testing and sample requirements that generate that evidence. |
| Change control plan | How changes are classified, assessed, decided and recorded. | Substitution rules and a revision process that produce the inputs the plan assumes. |
The guidance does not list the specification as a standalone upload. The compliance statement and fire and emergency file are the documents most likely to depend on it. Check the current Building Safety Regulator guidance on what must be uploaded.
The BSR also lists the problems it sees most often, including undescribed key connections, unevidenced fire performance of cladding, walls and cavity barriers, and unproven smoke control. Several of these are specification problems: the product or system is named but the evidence for its performance is missing or does not match the installed configuration.
What must the specification evidence for Gateway 2?
For each safety-critical element the specification should show the required performance and its standard, the whole system and not just a headline product, and the classification, test or assessment that supports it for the configuration actually proposed.
Specifications for ordinary buildings can describe a result and leave the evidence for submittals. At Gateway 2 the evidence question comes forward, because the compliance statement has to explain why the chosen approach complies. The specification should make three things visible for every safety-critical element: the performance required, the product or system that will achieve it, and the evidence that it does.
Run the check for each safety-critical element
- Performance: Is the required value stated, with the standard it is measured against? Fire resistance, reaction to fire, structural capacity, smoke control, and acoustic or thermal values where they feed the compliance route.
- System: Is the whole system described, not just the headline product? Cavity barriers, fire stopping, fixings, brackets, membranes and insulation are part of the evidence.
- Evidence: Is the classification, test or assessment named, and is it for the configuration to be built? A report for a different substrate or build-up is not evidence for this wall.
- Source: Does the specification say which document governs? The fire strategy, the structural report, or the specification itself.
- Drawings: Do identifiers, notes and values agree with the specification? A drawing note that restates a requirement creates a second version.
- Responsibility: Is the author of each design item named, with its inputs and deliverables?
- Change: Is it clear how a substitution would be assessed against the approved position?
Run these seven questions on each external wall, compartment line, escape route and smoke control element before the compliance statement is finalised.
Performance and classification
Say what the element must achieve and state the classification route explicitly. Fire performance is normally expressed through the BS EN 13501 series, with reaction to fire in part 1 and fire resistance in part 2. Regulation 7(2) of the Building Regulations 2010 restricts the reaction to fire of materials in the external walls of certain buildings, and the scope of those restrictions has changed over time. Check the current wording of the regulation and the relevant guidance before quoting thresholds. The Approved Document B guide and the fire strategy report guide set out how those requirements enter the design.
Products named once, with the system around them
A named product without its interfaces cannot show compliance. The specification should name the products and the accessories, fixings and details that make the tested system. Where the tested configuration includes a particular cavity barrier or fixing spacing, say so and make the installation requirement match. If alternatives are permitted, define equivalence in terms of the same classification, for the same configuration, and say who assesses it.
Evidence the specification asks for, and when
Gateway 2 is not the end of the evidence trail. The construction control plan has to list the evidence expected during construction and who will collect it, and the Gateway 3 completion application relies on the same record. The specification can feed both by stating the submittals, the samples, the test regime and the as-built evidence for each safety-critical element. This is also where a pre-issue technical review pays for itself, because the same comparison that finds a mismatch with the schedules finds a missing classification.
How much contractor-designed work has to be resolved before Gateway 2?
It has to be resolved far enough for the BSR to see how the element will comply. If it cannot be, the options are earlier specialist input, a staged application, or approval with requirements, and the specification should say which parts are still open.
On many higher-risk buildings the cladding, the fire stopping, the smoke control and the services are designed by specialists after the main design stage. That conflicts with a regime that wants the design shown to comply before work starts. The specification has to bridge the gap, and the choice is between resolving enough of the design early and structuring the application so that unresolved parts do not hold up the rest.
- 01
Develop with the specialist before submission
Appoint or consult the specialist early so that the design shown at Gateway 2 is the design that will be built.
- Specification effect
- Detailed performance and system description, tested configuration named
- Trade-off
- Earlier cost and programme commitment
- 02
Apply in stages
The BSR allows staged applications for new buildings, with detailed plans for each stage before work on it starts.
- Specification effect
- Specification sections issued stage by stage with a clear boundary
- Trade-off
- Several decisions and several change logs to manage
- 03
Approval with requirements
The BSR can approve with requirements, so work starts on approved parts while the rest awaits further information.
- Specification effect
- Unresolved packages identified with the information still to come
- Trade-off
- Work on those parts cannot start until the requirement is met
The BSR sets the rules for staged applications and for approval with requirements. Speak to the BSR before choosing a staged route for multiple towers.
The CDP performance specification guide explains how to write the requirements for contractor-designed work. For Gateway 2 the points to add are these. State the performance and evidence for the element at the level the compliance statement needs. Identify which parts remain to be designed and which standards govern them. Record which package the BSR is being asked to approve now and which it will see later, so that the specification, the drawings and the application agree.
The BSR can also reject an application that lacks enough detail to decide. A specification that says "design by specialist, to comply with Building Regulations" is exactly that kind of gap. Treat "to comply with" as an unfinished requirement. The related design responsibility matrix is the place to show who is completing each design item, and when.
What happens to the specification after approval?
After approval the application documents are the agreed documents. Product substitutions and other specification changes are controlled changes and fall into recordable, notifiable or major tiers depending on their effect on compliance.
Once the BSR approves the application, the documents become the agreed documents, and any change to them is a controlled change. The BSR's guidance on making changes to a higher-risk building project sets three tiers. The specification is where most of the day-to-day changes arise, particularly product substitutions, so the tiers matter to whoever manages the specification during construction.
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| Type of specification change | Likely tier under BSR guidance | Why |
|---|---|---|
| Product replaced with another of the same or higher specification or class | Recordable, entered in the change control log | The guidance treats same or higher specification and class as recordable. |
| Product replaced with a different reaction to fire specification, even a higher one | May be notifiable, tell the BSR before the work starts | The guidance says a different reaction to fire specification may be notifiable even if higher. |
| Product replaced with a lower reaction to fire specification and classification than approved | Major, BSR approval before the work starts | Listed as a major change. |
| Change to the external walls, including wall ties, restraint fixings and support systems | Major | Listed as a major change. |
| Change to active or passive fire safety measures referred to in the fire and emergency file | Major | Listed as a major change. |
| Change to assumptions in the compliance statement | Major | Listed as a major change. |
| Change to the number or dimensions of openings for pipes, ducts or cables | Notifiable | Listed as notifiable. |
| Wall tie, restraint fixing or support system in a wall other than an external wall | Notifiable | Listed as notifiable. |
Indicative reading of the BSR's published guidance. Classify each real change against the project's own change control plan and, where in doubt, ask the BSR. Check the tier wording against the current guidance.
For a major change the applicant must stop related work and wait for approval, and the BSR has up to six weeks to assess unless an extension is agreed. For a notifiable change the notice goes in before the work starts, and the work can proceed once it is submitted. The BSR can tell the applicant it should have applied for a major change, in which case work stops. A change submission needs a description, the reason, all the advice sought including advice that disagrees with the proposal, the affected agreed documents and an explanation of how the building will comply after the change.
The specification point is simple. A substitution request is a change request. Decide at contract stage who assesses it against the approved position, what evidence the contractor must supply, and who classifies it. The specification change control guide covers the process, and the Gateway 2 submissions guide sets out the three tiers in the wider regime.
How does the golden thread change the way a specification is kept?
The specification becomes part of a record that must stay accurate, traceable and complete. Issue it as a versioned document, supersede rather than overwrite, keep one source for each requirement and use consistent terminology across the document set.
On a higher-risk building the client has a legal duty under regulation 31 of the Gateway regulations to keep the golden thread electronically during design and construction. The golden thread guide covers the duty in full. For the specification, three practical consequences follow.
- 1
Before Gateway 2
Specification issued as a controlled, versioned document with a stated status, date and author.
- 2
Approval
The version submitted or referenced is identifiable. A later edit never replaces it.
- 3
Construction
Each change is a new revision linked to the change control log, with the earlier version kept.
- 4
Completion
Updated agreed documents and the change log are available for the completion application.
- 5
Handover
As-built product and system information passes to the accountable person with the thread.
The regulations treat earlier versions of updated documents as part of the thread, so the specification is superseded, not overwritten.
Version and supersede
Do not overwrite the issued specification. Each revision has an identifier, a date, an author and a reason, and the previous version stays available. This is also what makes the change control log meaningful, because the log must record which agreed documents each change affects and confirm that revised versions have been produced.
One source for each requirement
A performance value stated in the specification, the fire strategy and a drawing note will diverge. Choose where each value lives and cross-refer from the others. Single sources make the golden thread principle of one authoritative version practical and reduce the number of documents that a change touches.
Terminology and keys
The regulations expect information to be understandable to the people who use it, with consistent terminology where practicable. Use the same names for systems and elements across the specification, drawings and compliance statement, and keep an index or key where codes are used.
Questions technical directors ask about Gateway 2 specifications
Is the specification a mandatory Gateway 2 document?
The Building Safety Regulator's guidance on preparing a building control approval application lists drawings and plans, a compliance statement, a fire and emergency file, a construction control plan, a change control plan, a mandatory occurrence reporting plan and other documents. It does not list the specification as a separate upload. In practice the specification, or extracts from it, is commonly referenced by the compliance statement as evidence of products and performance. Confirm current expectations with the Regulator and the principal designer.
What does the specification need to show for the building regulations compliance statement?
The compliance statement sets out, for each element, how the work meets the relevant functional requirements, which guidance or standards are followed and why. The specification supports that by stating the performance, the products or systems, the standards and the test or classification evidence for each element, and by agreeing with the drawings the statement refers to.
Do contractor-designed elements have to be resolved before Gateway 2?
They have to be resolved far enough for the Regulator to see how they will comply. Where an element is unresolved, the application can be rejected for lack of detail. Options include developing the design with specialists before submission, applying in stages, or relying on approval with requirements, which the Regulator may grant so that work can start on approved parts.
What counts as a major change to a specification after approval?
Replacing a product with one that has a lower reaction to fire specification and performance classification than the one in the approved application is a major change and needs the Regulator's approval before the work starts. Changes to the external walls, the fire safety measures in the fire and emergency file, the structure, the stairs and escape routes, and assumptions in the compliance statement are also listed as major. Check the current Regulator guidance for the full list.
What is the difference between a notifiable change and a recordable change?
A notifiable change must be submitted to the Regulator before the work starts, and the work can proceed once it is submitted. A recordable change is logged in the change control log, which the principal contractor keeps. Replacing a product with one of the same or higher specification or class is recordable, but a different reaction to fire specification, even a higher one, may be notifiable.
Does the specification form part of the golden thread?
On a higher-risk building the design information, the approved documents and the record of changes all form part of the golden thread that the client must keep under the Gateway regulations. A specification issued as a controlled, versioned document with superseded revisions retained supports that duty, and an overwritten file does not.
Where Avoice fits
Gateway 2 rewards a specification whose claims can be traced to evidence, and the golden thread rewards a record kept as the work happens. Both are comparison and record-keeping tasks.
Avoice's Compliance module includes Gateway 2 support, a building regs tracker that links each requirement to its evidence, a Project Record that logs documents and decisions with their date and author, and a golden thread view and export. The specification is written in the same project, so a compliance claim can point to the clause that carries the product and performance.
The pre-issue Technical Review compares the specification against schedules and drawings, which catches the mismatches that undermine a compliance statement, and practice rules can require a classification or test reference on safety-critical clauses. Construction Admin tracks submittals and specification changes during the build, so a substitution has a record before anyone asks which tier it falls into.
Software can link, compare and log. The client and the dutyholders remain responsible for the application, and the BSR decides whether it is adequate.