How to Upgrade Fire Doors Without Compromising Safety

A fire door can look serviceable while offering little reliable resistance to fire or smoke. For building owners, principal contractors and facilities teams, knowing how to upgrade fire doors starts with a simple principle: a door assembly is only as effective as its weakest component. The leaf, frame, ironmongery, seals, glazing, installation and maintenance history must work together as a tested and evidenced system.

Upgrading is not a cosmetic exercise and should not be approached as a series of isolated repairs. A poorly selected closer, incompatible intumescent strip or excessive perimeter gap can undermine the performance expected of the door. The objective is to reinstate, or where evidence permits improve, the fire-resisting and smoke-control performance required by the building’s fire strategy.

Start with a competent fire door survey

Before specifying any work, establish what is already in place. A detailed survey identifies the door’s location, intended rating, condition, construction, defects and suitability for upgrade. It should also consider how the building is used, whether it is occupied during works, and the consequences of a door failing on an escape route, compartment line or protected shaft.

A survey should record the door leaf and frame dimensions, identifying marks, glazing, apertures, hinges, locks, latches, closers, seals, thresholds and visible gaps. Previous alterations matter. A letter plate, access-control device, viewer, rebated meeting stile or unauthorised cut-out may have changed the performance of the original assembly.

The survey must be read alongside the fire strategy, compartmentation drawings and relevant project information. A door marked FD30 is not automatically appropriate simply because it is located in a corridor. Its required performance depends on its purpose and location, and may include smoke leakage control as well as fire resistance. Where the original specification cannot be verified, the survey should identify the evidence needed before an upgrade is proposed.

Decide whether upgrading is justified

Not every existing fire door should be upgraded. In many refurbishment projects, retention is valuable: it can reduce programme disruption, preserve heritage fabric and avoid unnecessary replacement. This is particularly relevant in listed buildings, hotels, education settings and occupied residential properties, where original joinery may form part of the building’s character.

However, retention is only defensible where the door can achieve the required performance through a recognised and compatible upgrade route. The proposed solution should be supported by test evidence, assessment, manufacturer guidance or a suitable certification scheme. A nominal rating stamped on a leaf, an old label or an assumption based on thickness is not enough.

Replacement is often the safer option where there is extensive delamination, warping, damage at hinges or locks, unverified core construction, excessive trimming, failed glazing, significant frame defects or multiple historic alterations. The cost comparison must include more than the price of a new door. Consider programme, making good, access control, finishes, resident communication, temporary protection and the risk of rework after inspection.

Upgrade the complete door assembly

A fire door does not perform as a leaf in isolation. Its performance relies on the interaction between all components. Any upgrade specification should therefore set out the whole assembly, including permitted products and installation details, rather than issuing a general instruction to ‘make good fire doors’.

Door leaf and frame

The leaf must be sound, correctly fitted and compatible with the frame. Damage around the lock block, hinge recesses and bottom edge can be particularly consequential because these areas are subjected to repeated use. Frames must be securely fixed to the supporting construction and have an appropriate fire-stopping detail at the perimeter. A high-performing leaf in a poorly fixed frame, or a frame with unsealed perimeter voids, is not a dependable barrier.

Excessive gaps require careful attention. The acceptable clearance depends on the tested system and the location of the gap. It is not appropriate to pack gaps with arbitrary timber, foam or sealant products. Compatible lippings, intumescent materials or adjustment of the assembly may be required, but each intervention must be supported by evidence for that door type.

Intumescent and smoke seals

Intumescent seals expand in heat to help close the gaps around a door leaf. Where cold smoke protection is required, combined intumescent and smoke seals or separate smoke seals may be specified. Their type, size, position and continuity are critical.

Seals should not be painted over, loosely fixed, missing at corners or interrupted without evidence. Installing larger seals than specified is not automatically safer: it can prevent the door closing fully or create pressure that affects operation. The door must close positively onto its latch from any practical opening position, without being forced or wedged.

Ironmongery and self-closing devices

Hinges, latches, closers, locks and access-control components are functional parts of the fire door system. They must be correctly selected, securely fixed and appropriate for the door’s rating, weight and use. Three hinges may be required for many assemblies, but quantity alone is not a specification. The hinge type, fixing method and compatibility with the leaf and frame matter.

Self-closing devices need particular scrutiny in occupied buildings. A closer that is set too aggressively creates access problems and encourages people to wedge the door open. One that is too weak may fail to overcome latch pressure, seals or air movement. Hold-open devices should only be used where they are designed for the purpose and release on activation of the fire alarm system.

Glazing, apertures and thresholds

Vision panels, letter plates, air-transfer grilles and other openings are common sources of non-compliance. Fire-resisting glazing must be installed with the correct glass, beads, seals and fixing details. Replacing broken glass with an apparently similar product can invalidate the performance of the assembly.

Threshold details deserve the same care. A large undercut can affect smoke control, while an unsuitable drop seal or threshold plate can obstruct access or prevent proper closing. The required solution depends on the door’s fire and smoke performance, floor finish, accessibility requirements and tested construction.

Control the works through evidence and quality assurance

Fire door upgrading should be managed as safety-critical work, not a finishing trade package. The specification should identify the required performance, approved upgrade method, products, substrates, installation sequence, inspection points and evidence to be handed over.

Third party approved installation provides valuable assurance, but it does not remove the need for project-specific control. Site teams should verify each opening before work begins, particularly in older buildings where dimensions, wall build-ups and concealed defects vary from room to room. Any departure from the approved detail should be referred back for technical review rather than resolved through improvised site changes.

Quality records should include door schedules, photographs before and after work, product information, batch or traceability details where applicable, inspection records, defects closed out and clear maintenance information. This evidence supports compliance, assists future facilities teams and demonstrates that the compartment line has been treated as a managed system.

For higher-risk or complex schemes, coordinate fire door works with adjacent passive fire protection. Service penetrations around frames, cavity barriers above ceilings, wall interfaces and fire-stopping at structural junctions all affect the continuity of compartmentation. ATOL Construction approaches this interface as one protective line, rather than separate packages with gaps in responsibility.

Account for regulations, use and building constraints

The applicable requirements will vary across the UK and according to building type, height, use and scope of work. In England, Building Regulations guidance, the Regulatory Reform (Fire Safety) Order and the building’s fire-risk assessment may all influence the required approach. Design teams and responsible persons should confirm the relevant standards and fire strategy rather than relying on a generic upgrade schedule.

Heritage projects need additional care. Retaining historic leaves and frames can be achievable, but interventions must protect both the significance of the fabric and the fire strategy. Concealed intumescent upgrades, sympathetic repairs and carefully chosen ironmongery may be possible, subject to suitable evidence. Where performance cannot be demonstrated, preservation alone cannot justify an unreliable escape or compartment door.

Keep upgraded doors effective after handover

A compliant installation can deteriorate quickly where doors are subjected to heavy traffic, deliveries, misuse or unmanaged alterations. Facilities teams should incorporate fire doors into planned inspection and maintenance regimes. Check that doors close and latch, seals remain intact, glazing is undamaged, gaps remain within the intended tolerances and no one has fitted unauthorised hardware or wedged doors open.

The most reliable route to safer fire doors is a survey-led decision, an evidence-based specification and accountable installation. Treat every opening as part of the final barrier between a building and fire, and the upgrade will protect more than compliance: it will help protect people, property and the continuity of the organisation within it.