Fire-rated doors for new builds are available in standard sizes, but industrial applications frequently require custom dimensions. Most manufacturers offer standard single-leaf widths from around 900 mm to 1,200 mm and heights from 2,000 mm to 2,500 mm. For industrial new builds — logistics centres, production halls, warehouses — openings regularly exceed these ranges, making custom sizing the norm rather than the exception. The sections below cover the most common dimensions, how sizing interacts with fire resistance classification, and how to specify fire door dimensions correctly at the design stage.
Are fire-rated doors available in standard sizes?
Yes, fire-rated doors are available in standard sizes, but the range is narrower than many architects expect. Standard single-leaf fire doors typically span widths of 900 mm to 1,200 mm and heights of 2,000 mm to 2,500 mm. These dimensions suit office corridors, stairwells, and smaller commercial openings, but they rarely align with the structural openings found in industrial new builds.
In industrial construction — production halls, logistics centres, healthcare complexes with service zones — door openings are sized around operational requirements: forklift passage, goods transport, equipment access, and emergency egress. Those requirements routinely produce opening widths of 3,000 mm or more, and clear heights that exceed 4,000 mm. For these applications, a catalogued standard size is a starting point for specification, not a complete answer.
Manufacturers that design fire-rated industrial doors with in-house R&D capability can produce certified solutions well beyond standard dimensions. Metacon-Next’s fire-rated door range covers roller doors, overhead doors, sliding doors, and fire curtains — all manufactured to order and tested to EN 1634-1, meaning custom dimensions do not compromise the fire resistance classification.
What dimensions are most common for industrial fire doors?
The most common industrial fire door dimensions depend on the application. Single-leaf industrial fire doors typically range from 1,000 mm to 1,500 mm wide and 2,200 mm to 3,000 mm tall. Double-leaf configurations extend effective clear widths to 2,500 mm or more. For vehicle and forklift passage, clear widths of 3,000 mm to 5,000 mm are standard, with heights of 4,000 mm to 6,000 mm common in warehouse and production environments.
Fire curtains and fire-rated roller doors are particularly well suited to large industrial openings because they roll up into a compact housing above the opening, preserving clear height during normal operations. This makes them a practical choice wherever forklift traffic, internal transport, or wide goods movement must pass through a fire-compartment boundary without obstruction.
Sliding fire doors offer another solution for wide openings where a roller configuration is not structurally feasible. These doors park alongside the wall when open and close automatically on fire alarm activation, maintaining compartmentation without interrupting workflow during normal operations.
For architects specifying industrial fire doors, the critical starting point is the structural opening dimension confirmed by the structural engineer — not a catalogue dimension. Once the clear opening is fixed, the door system is selected to match it, not the other way around. Visiting Metacon-Next’s website gives access to technical documentation and dimensional ranges across product types, which can inform specification at an early design stage.
What’s the difference between standard and custom fire door sizes?
The difference between standard and custom fire door sizes lies in whether the door is produced from a fixed catalogue dimension or manufactured to a project-specific opening. Standard sizes are pre-tested at those exact dimensions and can be delivered faster. Custom sizes are manufactured to the specified opening and must fall within the extended application of assessment (EXAP) range defined in the product’s classification report to retain the fire resistance rating.
This distinction matters for specification integrity. A fire door’s CE marking and classification report are tied to the tested configuration — including its dimensions. If a custom size falls outside the EXAP range, a new test or a separate assessment is required. Architects specifying non-standard dimensions should confirm with the manufacturer that the requested size is covered by the existing classification documentation before including it in the permit-ready design file.
In practice, leading industrial fire door manufacturers design their products with wide EXAP ranges precisely because industrial openings vary so significantly from project to project. Custom sizing within that range carries the same classification as the tested standard — EI1 60, EI2 60, EI1 90, or whichever class the project requires — without additional testing or certification delays. Which classification is required for a specific project depends on the fire safety calculation for that building; a qualified fire safety engineer or the local authority is the appropriate point of reference for that determination.
For architects who need to verify dimensional coverage quickly, Metacon-Next’s product range includes full classification reports and technical documentation that specify the applicable dimension ranges per product type.
Do fire door dimensions affect the fire resistance classification?
Fire door dimensions do not automatically change the fire resistance classification, but they must remain within the limits defined in the product’s classification report. A door tested and classified as EI1 60 retains that classification for any dimension within its EXAP range. If the specified opening exceeds that range, the classification can no longer be applied, and the architect must seek a separately tested or assessed solution.
The fire resistance classification itself — EW, EI1, or EI2 at a given duration such as 30, 60, or 90 minutes — is determined by the project’s fire safety calculation, not by the door’s physical size. These classifications are defined per EN 13501-2 and describe how long a closed door holds back fire: E (integrity — no flames or hot gases pass through), W (radiation reduction — limits radiant heat transfer through the door; this is the Dutch standard baseline criterion), EI1 (insulation, stricter criterion — limits temperature rise on the unexposed side to a lower threshold), and EI2 (insulation, less strict criterion — a higher temperature rise on the unexposed side is permitted). Neither criterion is inherently linked to door width or height. Which classification is appropriate for a given application depends on the project-specific fire safety calculation; consult a qualified fire safety engineer or Metacon-Next directly for project-specific guidance.
What dimensions do affect is the structural and mechanical design of the door. Larger doors require heavier leaf constructions, more robust hardware, and in some cases, different closing mechanisms to ensure reliable self-closing performance under fire conditions. These engineering considerations are resolved at the manufacturing stage, but they are relevant when reviewing lead times and technical feasibility at the specification stage.
Architects working on large-opening specifications can use Metacon-Next’s technical contact to confirm whether a specific dimension and classification combination is covered by existing certification before committing to a specification.
How should architects specify fire door sizes in a new build design?
Architects should specify fire door sizes in a new build by defining the required clear opening dimensions — width and height — based on operational and structural requirements, then selecting a certified door system whose classification report covers those dimensions. The specification should reference the fire resistance class (for example EI1 60 or EI2 90), the door type, the structural opening size, and the required certification documentation including the CE declaration and classification report. Note that for industrial fire doors, two CE-relevant standards apply simultaneously: EN 16034 (fire- and smoke-resistant closing element) and EN 13241 (industrial door, general) — both should be referenced in the specification rather than treating them as interchangeable.
Start with the structural opening, not the door leaf
The structural opening is determined by the building’s use, traffic flow, and fire compartment layout — not by what a manufacturer catalogues. Define the minimum clear width and height needed for the intended use, add the required frame and installation tolerances, and arrive at the structural opening dimension that goes into the architectural drawing. This sequence prevents the common error of specifying a door that physically fits but requires the structural opening to be reduced after the permit stage.
Confirm classification coverage before finalising the specification
Once the opening dimension is fixed, verify that the chosen product’s classification report covers that dimension under its EXAP provisions. Request the full classification report — not just the CE declaration — at the specification stage. For industrial projects with atypical openings, this step can save significant time during the permit review. Manufacturers with transparent documentation practices make this straightforward: Metacon-Next publishes classification reports and EPDs for its product range, which architects can review without requesting them individually.
Include dimensional tolerances and frame details in the specification
A complete fire door specification for a new build should include the structural opening dimensions, the required clear passage dimensions, the frame type and installation method, and any specific hardware requirements such as hold-open devices, automatic closing on alarm, or glazing. These details define the scope for the installer and prevent substitutions during construction that could compromise the fire resistance classification.
For architects who need to generate specification-ready technical information efficiently, requesting a quotation from Metacon-Next provides access to dimensional data, BIM files, and technical drawings through the MetaConfigurator portal — available without extended back-and-forth correspondence. This is particularly useful at the tender stage, when specification documents need to be complete before a contractor is appointed.
Specifying fire door dimensions correctly at the design stage is one of the clearest ways an architect can protect the integrity of the permit file and avoid corrections during fire safety review. Working with a manufacturer whose documentation is complete and publicly available — and whose product range covers the full scope of industrial opening types — removes a significant source of specification risk. Metacon-Next’s background as a Dutch manufacturer with nearly a century of production heritage and an in-house R&D department means that technical questions about dimensions, classifications, and certification are answered directly by the manufacturer, not relayed through a distributor chain.
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