Nominal vs Notional Fire Doors: What’s the Difference and Why Certified Always Wins

The three types of fire door compared

Every fire door in a building falls into one of three groups, depending on the evidence behind it.

What is a certified fire door?

A certified fire door is a fire door assembly whose design has been fire tested – to BS 476-22 or BS EN 1634-1, and for smoke control (the “S” in FD30S) to BS 476-31.1 or BS EN 1634-3 – and which is manufactured under a third-party certification scheme.

Third-party certification goes further than a one-off test. The BWF Fire Door Alliance explains that the manufacturer is independently audited to make sure its processes stay consistent with the product that was tested, and that standard products are tested again regularly, so the original test was not a once-only event.

A certified fire door can be identified. The certification label is usually on the top edge of the door leaf, or in the frame for complete factory-made assemblies. It shows the manufacturer, the certificate number, a unique serial number and the fire rating, so the door can be traced back through the supply chain. When it is installed with the frame, ironmongery, seals and glazing covered by the same certification, you have evidence that the whole assembly will do its job.

What is a notional fire door?

A notional fire door is an older door that satisfied the fire door specification, or fire resistance test, for its rating at the time the building was constructed or the door was made. You will often see them recorded as “notional FD30” in fire risk assessments for older blocks of flats.

The problem is not that these doors were badly made. Many were well built to the standards of their day. The problem is evidence. There is usually no label, no certificate and no data sheet, the original paperwork has long gone, and many have no intumescent strips or smoke seals. After decades of use, repairs, new locks and replacement hinges, nobody can say for certain what is inside the door or how it would perform in a fire today.

What is a nominal fire door?

A nominal fire door has no evidence that it ever met a fire door standard. Instead, a competent fire door inspector or assessor forms an opinion that it can provide a degree of fire resistance, based on what they can see – for example a solid, close-fitting timber leaf of a reasonable thickness, hung in a sound frame with an adequate door stop.

Nominal doors are common in older houses, HMOs and converted properties, where an original solid door has been kept and treated as a fire door. Of the three types, a nominal door carries the least certainty, because its performance rests entirely on judgement.

Nominal vs notional: the key difference

The difference comes down to history:

• A notional fire door was intended to be a fire door. It met a recognised specification when it was installed, even though that can no longer be proven.
• A nominal fire door may never have been intended as a fire door at all. It is treated as one because an inspector believes it can resist fire for a period.

What they have in common matters more. With both, fire performance is presumed, not proven. Neither can show test evidence, a certificate or a traceable label. That is exactly what separates them from a certified fire door.

Can notional and nominal fire doors still be accepted?

In existing buildings, sometimes – and it is important to be honest about this. Welsh Government guidance for responsible persons notes that fire doors installed when a building was constructed “may well be compliant”, while advising that this is checked as part of the fire risk assessment, especially in older premises. Surveyors writing for RICS have also warned against ripping out sound existing fire doors and frames as a blanket recommendation.

So a notional or nominal door is not automatically unlawful. Whether it is acceptable depends on:

• the findings of a suitable and sufficient fire risk assessment;
• where the door is – a flat entrance door onto a single escape stair carries far more risk than a cupboard door;
• its condition: no damage, splits, poor repairs or excessive gaps;
• whether it closes fully and latches every time under its self-closer;
• whether any upgrades, such as intumescent strips and smoke seals, have been fitted properly;
• whether the decision has been recorded and the door is inspected and maintained regularly.

Acceptance is a judgement made for one door, in one building, at one point in time. It is not evidence of performance.

Why certified always wins

When a door is being installed or replaced – or when an existing door fails inspection – there is no contest. A certified fire door assembly wins for six reasons:

1. Proof, not opinion. A certified fire door assembly has test evidence and independent certification behind it. A notional or nominal door has an assumption.
2. Evidence cannot be backdated. Adding strips, seals or new hinges can improve an old door, but it cannot create test evidence or certification for it. The only way to get a certified fire door is to fit one.
3. It matches BS 8214:2026. The 2026 code of practice places a clear focus on verification. Every new installation must have evidence that all its components – leaf, frame, ironmongery, seals and glazing – have been tested together as one fire door assembly.
4. Traceability. The label links the door to its manufacturer, certificate and rating, so inspectors, fire risk assessors and insurers can check it in seconds.
5. Clearer compliance records. Responsible Persons must keep fire doors in good repair and, in many residential buildings, have them checked regularly. Inspecting a certified door against its certification is far more straightforward than defending a judgement call.
6. Better value over time. Repeatedly upgrading, repairing and re-justifying a door with no evidence often costs more in the long run than fitting a certified assembly once and maintaining it properly.

What to do if your building has notional or nominal fire doors

1. Find out what you have. Book a fire door inspection in Liverpool to identify which doors are certified, notional or nominal, with a written, dated record for each door.
2. Check your fire risk assessment. Make sure it says whether each notional or nominal door is acceptable in its location, and why.
3. Maintain the doors you keep. Keep accepted doors closing, latching and sealing properly. Our fire door maintenance service covers repairs and adjustments.
4. Replace with certified assemblies. Where a door fails, is damaged or sits in a high-risk location, replace it with a complete certified fire door assembly.
5. Keep the paperwork. Store certificates, data sheets, inspection reports and sign-off documentation for every door.

How Liverpool Joinery Services can help

We are UK Fire Door trained and FireQual-certified fire door specialists with over 20 years’ experience, working across Liverpool and Merseyside. We inspect existing doors and tell you clearly whether they are certified, notional or nominal. Where replacement is needed, we install certified fire door assemblies with sign-off documentation for your records.

Many older Liverpool buildings have large period doorways that standard doors do not fit. We make certified fire door assemblies to suit those openings and keep original features where possible – see our Victorian and period fire doors. For the wider picture on the new code of practice, read BS 8214:2026 explained.