Double, Sliding and Other Fire Door Configurations

Can fire doors be double, sliding or other configurations?

Yes. A fire door is not restricted to a single hinged leaf. England's Approved Document B makes this explicit in its own glossary: 'A fire doorset may have one or more leaves,' and it is 'a complete door assembly, assembled on site or delivered as a completed assembly, consisting of the door frame, leaf or leaves, essential hardware, edge seals and glazing.' Double-leaf pairs are commonplace, and sliding and other powered configurations are available for specific settings. The catch is evidential: the fire rating belongs to the configuration that was tested, not to a leaf in isolation.

That is the single most important rule on this page. Under both BS EN 1634-1 and the older BS 476-22 route, a specimen is tested as a complete assembly in a furnace, so the classification is earned by that exact combination. The BWF Fire Door Alliance puts it plainly: a door 'is tested as a complete assembly or doorset in a test furnace and can only work correctly if installed using the same compatible components as when it was tested.' A pair introduces a second leaf and a meeting stile that a single-leaf test never saw — so you cannot assume a single-door test covers a pair. Approved Document B reinforces this in Appendix C: test evidence must be checked to ensure it is 'applicable to the complete installed assembly. Small differences in detail may significantly affect the rating.'

The rating itself — for example the FD30 shorthand, corresponding to E30 integrity under BS EN 13501-2, not the insulated EI30 class — attaches to the whole configuration as tested. The table below sets out what each configuration adds on top of a certified single fire door.

What makes a pair of fire doors different from two single doors?

A pair is not two single doors hung in one opening. The difference is the meeting stile — the vertical junction where the two leaves come together — which has to resist fire and smoke as reliably as the rest of the assembly. There are two common approaches, and both must be part of the tested configuration.

Rebated, astragal and square meeting stiles

• Rebated meeting stiles overlap, so one leaf laps over the other to form a physical barrier across the joint. The overlap also fixes a closing order: the leaves cannot shut in the wrong sequence without leaving the rebate proud, so a rebated pair needs a coordinator.
• Astragal meeting stiles use an applied strip (an astragal) fixed to one leaf to cover the gap between the two leaves, achieving a similar overlap where square-edged leaves are used.
• Square (butt) meeting stiles meet edge to edge and rely on the intumescent and smoke seals at the junction to close the gap when heat activates them.

In every case the meeting stile carries intumescent protection: strips let into the leaf edges (or the astragal) expand under heat to seal the central joint, with cold-smoke seals added where restricted smoke leakage is required. The BWF Fire Door Alliance Best Practice Guide stresses that the correct type and size of intumescent seal at the meeting stile is part of what makes a pair perform — swapping it changes the tested specification.

Because the pair, its meeting-stile detail, its seals and its coordinating hardware are all tested together, a certified pair is a different product from a certified single door. This is the same principle behind the difference between a fire doorset and a site-built assembly: what protects you is evidence for the thing actually in the wall. Ordering two single certified leaves and hanging them face to face does not create a certified pair, because no test covered that combination.

How do both leaves of a fire door pair close and latch correctly?

A single door only has to close and latch itself. A pair has to do that twice, in the right order, whichever leaf someone opened. Three pieces of hardware make that happen, and all of them are part of the certified configuration.

Both leaves self-closing

Approved Document B expects fire doorsets to be fitted with a self-closing device (with limited exceptions such as some cupboard and service-duct doors). On a pair, each leaf is a fire door leaf, so each needs its own self-closing device capable of closing it from any angle and, where the leaf latches, driving it into the latch. A pair with a closer on only one leaf will not reliably re-form the fire barrier after use.

A door coordinator to BS EN 1158

Where the meeting stiles are rebated or fitted with an astragal — or where the pair latches or uses flush bolts — the leaves must close in a set sequence. If they close in the wrong order, the rebate or astragal fouls and the leaves cannot fully shut, leaving a gap across the joint. A door coordinator (also called a sequence selector) is fitted at the head of the frame to hold back whichever leaf was released first, letting the other close home before releasing it. BS EN 1158, 'Building hardware. Door coordinator devices. Requirements and test methods', is the standard for these devices; those intended for fire and smoke doors carry the fire-rated classification within it and should be assessed for use on the relevant door type. The coordinator guarantees the correct closing sequence no matter which leaf is opened first.

Latching and securing the inactive leaf

On many pairs one leaf is the active (usually latched) leaf and the other is the inactive leaf, held shut top and bottom by flush bolts (also called shoot bolts). For fire duty these bolts should be fire-rated to BS EN 12051, 'Building hardware. Door and window bolts.' The coordinator then ensures the inactive leaf closes and bolts home before the active leaf latches over it. A practical checklist for a pair:

1. Both leaves self-closing — a certified closer on each leaf, adjusted to close and latch fully.
2. A door coordinator to BS EN 1158 wherever the meeting stiles are rebated or astragalled, or the pair latches or uses flush bolts.
3. Fire-rated flush bolts to BS EN 12051 securing the inactive leaf top and bottom.
4. Meeting-stile intumescent and smoke seals of the type and size in the certification, undamaged and continuous.
5. Compatible hardware matching the pair's certificate — hinges, closers, coordinator, bolts and latches as tested, not generic substitutes.

When are double fire doors the right choice?

Double doors earn their place where a single leaf cannot do the job. The usual drivers are practical rather than regulatory:

• Wide openings — an opening broader than a single leaf can span comfortably is served by two leaves rather than one oversized, heavy door.
• Traffic and accessibility — busy corridors, lobbies and cross-corridor doors move more people, and an inactive leaf can be released for larger or wheeled traffic when needed.
• Moving equipment — settings where beds, trolleys, stock or plant must pass through benefit from the extra clear width a pair provides when both leaves are open.

None of that relaxes the fire requirements. A wide compartment or corridor line still has to hold its fire and smoke resistance across the full opening, so the whole pair — both leaves, the frame, the meeting stile, the seals and the coordinating hardware — must be a certified configuration rated for the required period. The decision to use a pair is about width and use; the decision about certification is about proving that specific pair was tested.

Can fire doors be sliding or automatic — and how do they fail safe?

Sliding and automatic fire doors are permitted, but only where they are tested and certified in that form. BS EN 1634-1, the fire-resistance test method, applies to more than hinged doors: its scope covers 'horizontally sliding and vertically sliding doors', folding and sliding-folding doors alongside hinged and pivoted types. So a sliding fire door has its own test route — but a hinged door's evidence does not transfer to a sliding one, and vice versa. Sliding fire doors are found chiefly in some commercial, industrial and healthcare settings where a wide opening has to stay clear in daily use yet close completely in a fire.

Because a sliding leaf is not driven shut by a swing closer, the safety principle is different: it is normally held open and must close automatically and fail-safe. In practice the leaf is held open by an electromagnetic hold-open (or a heat-sensitive fusible link) and closes — under gravity, a counterweight, a spring or a motor — when released. The release must be fail-safe: interruption of power, or a fire alarm signal, drops the hold and lets the door close. That mirrors the rule for held-open swing fire doors, where hold-open devices to BS EN 1155 are built so that 'interruption of the electrical supply will cause the controlled door to close positively.'

The link between the fire alarm and any held-open or powered fire door is itself governed by a code of practice. BS 7273-4:2015+A2:2023, 'Code of practice for the operation of fire protection measures. Actuation of release mechanisms for doors,' gives recommendations for the electrical control arrangements that, on fire, 'release fire-resisting doors that are normally held in the open position', unlock doors that are normally locked, and 'cause powered sliding doors to open' on escape routes. It defines categories of actuation (A, B and C) with different fail-safe criteria: the most onerous requires reliable operation even on loss of both mains and standby power to the fire detection and alarm system. In short, a held-open or sliding fire door must not stay open when the alarm sounds or the power fails.

Two related products are deliberately out of scope here. Lift landing doors and roller shutters are separate configurations governed by their own product and test standards; pedestrian fire-doorset certification does not cover them, and they should be specified, certificated and maintained against the standards that apply to them.

How do you prove a non-standard configuration is certified?

The evidence trail for a pair, a sliding door or a held-open door is the same in kind as for any fire door, but it has to describe that configuration. A single-leaf certificate is not evidence for a pair, and a hinged-door certificate is not evidence for a sliding door. Warringtonfire explains how fire door performance is proven — through fire testing, third-party certification and, where a specimen differs from what was tested, an extended application report. As with any fire door, that means a fire-resistance test to BS EN 1634-1 (or the older BS 476-22), certification of the manufacturer, and a label or plug that ties the door to its documentation. For a non-standard configuration, check that the paperwork covers the exact thing installed:

1. A test or classification report for the configuration — a pair tested as a pair, or a sliding door tested as a sliding door, achieving the required integrity (and smoke) performance.
2. Scope that matches the opening — where the exact size or detail differs from the tested specimen, an assessment or extended application report covering that variation, produced from real test evidence rather than in place of it.
3. The coordinating and release hardware in the evidence — coordinator to BS EN 1158, flush bolts to BS EN 12051, hold-open to BS EN 1155, and, for powered or held-open doors, a BS 7273-4 actuation design and commissioning record.
4. A certification label or plug on the unit, protected during installation and never painted over or removed, linking the door to its certificate.
5. Installation and inspection records feeding the ongoing inspection regime, so the pair or powered door is checked as the configuration it is.

Get those in place and the principle from the top of this page holds up in practice: fire doors can be pairs, sliding or other configurations — provided the configuration in the wall is the one that was tested, and you can show it.