A connecting door between a warehouse and an office space is generally required to provide fire resistance because the two spaces typically form separate fire compartments under Dutch building regulations. The exact classification — EW, EI1, or EI2, and for how many minutes — is determined by a project-specific fire safety calculation, not a single fixed rule. The sections below walk through what the Dutch BBL (Besluit Bouwwerken Leefomgeving) prescribes, how classifications differ, and what documentation you need to close a permit file.
Which fire resistance classification applies to a warehouse-office separation?
A connecting door between a warehouse and an office must at minimum match the fire resistance requirement of the separating wall or floor it sits in. Under the BBL, that separation is typically required to achieve at least EW 30 or EI2 60, depending on the building use, occupancy category, and the outcome of the fire safety calculation. There is no single classification that applies universally to every warehouse-office situation.
The separation between a storage or production function and an office function almost always constitutes a compartment boundary. That boundary must limit the spread of fire and, in most cases, smoke. The door in that boundary must perform to the same level as the surrounding construction — which means the door classification is derived from the wall or floor classification, not chosen independently.
In practice, architects and fire safety advisors frequently encounter requirements of EI1 60 or EI2 60 for this type of separation, particularly in new construction. Higher classifications are possible when the warehouse stores hazardous substances, when sector-specific regulations such as PGS15 apply, or when the insurer or client imposes additional requirements beyond the statutory minimum.
What does the BBL say about connecting doors?
The BBL (Besluit Bouwwerken Leefomgeving, formerly Bouwbesluit) sets the absolute minimum fire resistance requirements for compartment boundaries, including the openings in those boundaries. A door in a compartment-separating construction must provide fire resistance equivalent to the required performance of that construction. The BBL does not prescribe a specific door classification by name — it defines the minimum requirement for the separation, and the door must comply with that requirement.
For industrial buildings, the BBL distinguishes between building functions, occupancy loads, and floor areas when determining compartment requirements. The decree sets an absolute minimum, but project-specific deviations, sector regulations such as PGS15, or client and insurer specifications can raise that minimum significantly. This is a point that frequently causes confusion: the BBL is a floor, not a ceiling.
Connecting doors are also subject to requirements on self-closing behaviour. A door in a compartment boundary must close automatically or be held open by a device that releases on fire alarm. This applies regardless of whether the door is manually operated or automated. Architects specifying fire-rated industrial doors need to confirm that the door’s operating mechanism complies with this requirement, not just its thermal and integrity performance.
What is the difference between EW, EI1, and EI2 for industrial doors?
EW, EI1, and EI2 are fire resistance classifications under EN 13501-2 that describe different levels of performance for separating elements such as doors. All three include the E criterion — integrity, meaning flames and hot gases are prevented from passing through. The W and I criteria then describe additional performance levels. These are not interchangeable classifications.
EW: integrity plus radiation reduction — the Dutch baseline criterion
An EW-classified door provides integrity — it prevents flames and hot gases from passing through — and limits radiant heat transfer to a level that reduces the risk of ignition on the unexposed side. EW is the Dutch standard baseline criterion for many compartment separations. However, the surface temperature on the unexposed face can still rise significantly, which means EW does not provide full thermal insulation. Whether EW is sufficient for a specific application depends on the project’s fire safety calculation, not on the door alone.
EI1 and EI2: full thermal insulation with different strictness levels
Both EI1 and EI2 require the door to maintain integrity and limit the average and maximum temperature rise on the unexposed face. The difference lies in the strictness of the insulation criterion: EI1 applies a stricter threshold for temperature rise on the unexposed side, while EI2 permits a higher temperature rise and is therefore the less strict of the two. For most industrial applications, EI2 60 is a common specification, but certain applications — particularly where people are expected to evacuate past the door or where the door forms part of a protected escape route — may require EI1. Always confirm with the fire safety advisor which criterion applies before finalising the door specification.
Specifying the wrong classification is a compliance risk. Always reference the fire safety calculation and confirm with the fire safety advisor which criterion applies before finalising the door specification.
How does a fire safety calculation determine the required door classification?
A fire safety calculation determines the required door classification by assessing the fire load, occupancy, compartment size, escape route design, and the consequences of fire spread between functions. The calculation is performed by a qualified fire safety engineer and results in a set of performance requirements for each separating element — including doors — expressed in terms of classification and duration.
For a warehouse-office separation specifically, the calculation considers factors such as the type and quantity of goods stored, the presence of sprinkler systems, the number of occupants and their proximity to the boundary, and whether the office forms part of an escape route. A sprinkler installation in the warehouse, for example, can influence the required fire resistance duration of the separation. Conversely, the absence of a sprinkler system in a high fire load environment typically results in higher requirements for the compartment boundary and its doors.
The fire safety calculation is a project document — it is specific to one building and one design. This is why blanket statements about which classification is required for a warehouse-office door are unreliable. The calculation is the authoritative source, and the door specification must follow from it. Architects should request the fire safety calculation output before finalising any door specification, and confirm that the specified product carries a tested and certified classification that meets or exceeds the calculated requirement. When in doubt, consult a qualified fire safety engineer or contact Metacon-Next directly.
What documentation does a fire-rated connecting door need for a building permit?
A fire-rated connecting door requires a CE declaration of performance, a classification report from an accredited testing body, and product-specific technical documentation as part of a building permit submission. In the Netherlands, the permit file must demonstrate that every product in a compartment boundary meets the required performance — and the door is no exception.
The classification report is the core document. It records the test conditions, the tested configuration, and the achieved classification in accordance with EN 13501-2. The CE declaration of performance links the product as supplied to that tested performance. For industrial fire doors, two CE-relevant standards apply simultaneously: EN 16034, which covers the fire- and smoke-resisting closing function, and EN 13241, which applies to industrial doors as a product category regardless of fire rating. Together with the classification report, these documents allow the permit reviewer and the building inspector to verify compliance without ambiguity.
Beyond the classification report and CE declaration, architects increasingly need Environmental Product Declarations (EPDs) for BREEAM or LEED assessments. An EPD is an information document — it describes the environmental impact of a product across its lifecycle — and does not constitute a sustainability award or label. Its presence in the permit file supports the broader sustainability documentation of the project.
Complete documentation at specification stage — rather than after order placement — is one of the most practical ways to avoid delays during permitting or fire safety review. Metacon-Next publishes classification reports, CE declarations, and EPDs for its product lines directly on its website, so architects can access and verify documentation without waiting for a supplier response. For projects requiring custom dimensions or atypical configurations, the full product range is supported by technical drawings and BIM files available through the MetaConfigurator portal.
If you are at specification stage and need to confirm which classification and documentation apply to your project, contact Metacon-Next directly or request a quotation with your project details. All products are supplied and installed through a certified dealer network, ensuring that both the product and its installation are fully documented and warranted from day one.
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