When a building undergoes a change of use, Dutch building regulations treat the altered section as if it were new construction for fire safety purposes. This means the fire safety requirements that apply to the new function take effect, not the rules that governed the original use. For architects and advisors specifying products at the design stage, understanding exactly which obligations this triggers is essential before a single door is selected.
What counts as a change of use under Dutch building regulations?
A change of use occurs when a building or part of a building is assigned a different user function as defined in the Besluit bouwwerken leefomgeving (BBL). The BBL categorises buildings by function, such as industrial, office, healthcare, or residential, and each function carries its own technical requirements. When the intended function changes, the applicable requirements change with it, regardless of whether the physical structure is altered.
In practice, this applies to a wide range of scenarios: a warehouse repurposed as a fulfilment centre with an office wing, a production hall converted into a data centre, or a logistics building adapted to store hazardous materials. Even partial changes matter. If only one section of a building changes function, that section is assessed against the requirements for its new function, while the rest of the building continues to be assessed under its existing classification.
The key trigger is the formal change in function as recorded in the environmental permit (omgevingsvergunning). If an activity changes but the registered function remains the same, the change-of-use rules may not automatically apply, though a fire safety engineer should always assess whether the actual risk profile has shifted materially.
Do fire safety requirements change when a building’s function changes?
Yes. When a building’s function changes, the fire safety requirements applicable to the new function apply to the affected part of the building. Under the BBL, the requirements for an existing building that undergoes a change of use are aligned with the requirements for new construction of that function type, not with the lower threshold that applies to existing buildings remaining in their original use.
This distinction is significant. Existing buildings are generally assessed against a lower baseline, reflecting the practical and financial constraints of retrofitting older structures. But once a change of use is registered, that leniency no longer applies to the altered section. The new function determines the required fire resistance durations, compartment sizes, escape route provisions, and the performance criteria for every fire-separating element, including doors.
In industrial contexts, this frequently means that fire compartmentation requirements become more demanding. A warehouse converted to store goods with a higher fire load, or a production hall repurposed for a use that brings more occupants into the building, will face stricter requirements than the original structure was designed to meet. Identifying those gaps early, at the specification stage, is what prevents costly redesigns or failed permit applications later.
Which fire resistance classifications apply to doors in a changed-use building?
The fire resistance classification required for a door in a changed-use building depends on the fire safety calculations for that specific project. There is no single classification that applies universally. The BBL sets only the absolute minimum requirements, but project-specific deviations from standard building regulations, sector-specific regulations such as PGS15 for chemical storage, and requirements set by insurers or clients can all impose stricter standards. The correct classification for any opening must be determined by a qualified fire safety engineer based on the actual project conditions.
That said, architects specifying doors for industrial and logistics applications will commonly encounter the following classifications under EN 13501-2:
- EW: The door provides integrity — stopping flames and hot gases — and limits radiant heat transfer through the door. EW60 is the Dutch standard baseline criterion for many industrial applications.
- EI2: The door provides integrity and thermal insulation, with a less strict temperature criterion on the unexposed face. This is a common and fully valid classification for industrial applications.
- EI1: The door provides integrity and thermal insulation, with a stricter temperature criterion on the unexposed face. EI1 applies where a lower temperature rise on the unexposed side is required.
The number following the classification — for example EI2-60 or EI2-90 — indicates the duration in minutes for which the door must maintain that performance, per EN 13501-2. A change of use that increases the fire load, reduces evacuation time, or introduces more vulnerable occupants may push requirements toward longer durations or a stricter insulation class. Whether a specific classification is sufficient for a given application depends on the project’s fire safety calculation, not on the door type alone. Always consult a qualified fire safety engineer or contact Metacon-Next directly for project-specific guidance.
Metacon-Next’s fire-rated industrial door range covers classifications including EW60, EW90, EW120, EW240, EI1-60, EI1-120, EI2-60, EI2-90, and EI2-120, across multiple door types — including roller curtains, roller doors, overhead doors, sliding doors, and pedestrian doors — and is suitable for large or atypical openings that standard products cannot accommodate, which is a common challenge in industrial change-of-use projects.
What documentation is required for fire-rated doors in a change-of-use project?
For a change-of-use project, fire-rated doors must be accompanied by a complete documentation set that demonstrates compliance at the time of specification, not after installation. The minimum required documentation includes a CE declaration of performance, a classification report from an accredited test body, and technical product data sufficient to verify that the installed product matches what was tested and certified.
For industrial fire doors, CE marking is governed by two standards that 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. Both are relevant and should not be treated as interchangeable or alternatives to each other.
In practice, architects working on permit-ready designs need the following from their door manufacturer:
- CE declaration of performance referencing EN 16034 and EN 13241
- Classification report issued by a recognised test body such as Efectis, based on testing per EN 1634-1 and classified per EN 13501-2
- Technical drawings showing installation dimensions, frame requirements, and threshold details
- Environmental Product Declaration (EPD) for projects with BREEAM or LEED requirements
- Maintenance documentation, since fire-rated doors are subject to periodic inspection obligations
One practical issue that frequently delays change-of-use projects is documentation arriving after the order is placed rather than at the specification stage. This creates problems during permit review and fire safety assessments, where the assessor needs to verify the product before installation, not after. Specifying a manufacturer that publishes its certificates, classification reports, and EPDs openly means this information is available when it is needed.
Metacon-Next makes its full documentation set publicly accessible — including Efectis classification reports, CE certificates, and EPDs published in 2025 — which allows architects to close a specification file without chasing documentation from a supplier. This is not standard practice across the industry, and the difference becomes visible precisely in the permitting phase of a change-of-use project.
When should a fire safety engineer be involved in a change-of-use project?
A fire safety engineer should be involved from the earliest design stage of a change-of-use project, before any products are specified and before compartmentation layouts are fixed. The reason is straightforward: the fire safety requirements for the new function cannot be determined without a project-specific fire safety calculation, and that calculation determines which classifications, compartment sizes, and door specifications are actually required.
Involving a fire safety engineer late in the process is one of the most common sources of costly redesigns in change-of-use projects. If compartmentation layouts are drawn and door specifications are written before the fire safety calculation is complete, there is a real risk that the specified products do not meet the requirements that the calculation eventually identifies. Correcting this at tender stage or during construction is far more expensive than resolving it at the design stage.
For architects, the practical implication is clear: treat the fire safety engineer as a design team member, not a reviewer. Their input defines the performance envelope within which every fire-separating element, including doors, must be specified. Once that envelope is established, selecting a manufacturer with the right certified product range, appropriate technical documentation, and the ability to supply custom dimensions becomes a straightforward specification task.
If you are working on a change-of-use project and need to verify whether a specific door product meets the classifications identified in your fire safety calculation, the Metacon-Next product range is fully documented and available for technical review. For project-specific questions or to request technical drawings, you can contact Metacon-Next directly or submit a quotation request through the website.
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