FD30 vs FD60 Fire Doors: Which Rating Should Your Design Specify?

24 September 2026

Choosing between an FD30 and an FD60 fire door is not a matter of picking the higher number for extra reassurance. The door has to suit the opening, the surrounding construction and the fire strategy for the building.

Both ratings describe performance under fire testing, but they represent different resistance periods. The distinction affects the doorset itself, its hardware and, in some cases, the demands placed on the frame and surrounding construction. For architects and project teams, the specification needs to start with what that particular opening is required to protect.

What Do FD30 and FD60 Ratings Mean?

An FD30 fire door has a 30-minute fire resistance rating under test conditions, while an FD60 door has a 60-minute rating. These figures describe test performance rather than guaranteeing how long a door will resist an actual fire. The rating applies to the doorset rather than the door leaf in isolation.

That distinction matters during specification. The frame, glazing, ironmongery, intumescent strips and other components can affect how the complete assembly performs. Scottish building standards guidance also makes clear that test evidence needs to apply to the complete installed assembly.

You may also see FD30S and FD60S. The “S” denotes a smoke control function. Smoke seals restrict the passage of smoke before heat causes the intumescent material around the door to expand. Scottish Government fire safety guidance uses FD30S and FD60S for doors tested with this additional smoke control function.

If you are dealing with existing fire doors and the available records do not confirm their rating or condition, book a fire safety inspection to have the doors, their components and any visible defects assessed before deciding what further action is needed. The findings can then be checked against the fire strategy and the requirements for each opening.

Where Does an FD30 Door Fit the Design?

FD30 provides the shorter of the two resistance periods, but that does not make it an inferior specification. Where 30 minutes of fire resistance is required, specifying an FD60 doorset instead does not remove the need to consider the rest of the wall, frame, hardware and escape strategy.

The question is what the opening needs to achieve. Does the door protect a route of escape? What level of fire resistance is required from the wall in which it sits? Does the design call for smoke control as well as fire resistance?

In Scotland, the Building Standards Technical Handbooks use short, medium and long fire resistance durations. Their tables relate short, medium and long fire resistance periods to different building elements and circumstances. The correct period still depends on the part of the guidance that applies to the building and opening concerned.

This is why an FD30 specification should come from the fire strategy and applicable building standards rather than from the assumption that 30 minutes is the default for every internal fire door.

When Does the Design Need FD60?

An FD60 doorset has a 60-minute fire resistance rating under test conditions. Scottish building standards use different fire resistance periods according to the building element and circumstances involved.

The surrounding construction matters just as much as the number on the door specification. A door forms part of an opening within a wall or compartment, so its required resistance needs to be considered alongside the performance expected from that construction.

That also means an FD60 door should not be treated as an automatic upgrade for every opening. Depending on the product, differences in the doorset can affect the frame, ironmongery and installation details without solving a specification problem elsewhere in the design.

Where 60 minutes is required, though, an FD30 doorset cannot substitute for it. The specified fire resistance period needs to follow the building design and the applicable fire safety requirements.

How Do the Doorsets Differ Beyond the Rating?

Both ratings need to be considered in relation to the complete doorset. The frame, hinges, closer, latch, glazing, intumescent material and any required smoke seals all need to be compatible with that doorset. The difference is not achieved by changing the door leaf alone.

An FD60 doorset may be thicker or heavier than an FD30 equivalent, depending on its construction and test evidence. That can affect hinge selection, frame details and installation. Component selection should follow the evidence for that doorset rather than a general rule about what every FD30 or FD60 door should contain.

The same principle applies to alterations. Changing glazing, ironmongery or other details can matter because fire resistance testing relates to the whole door assembly. Scottish technical guidance specifically identifies glazing apertures, intumescent strips, frames and ironmongery as details capable of affecting the rating.

For the designer, the product documentation matters just as much as the FD rating. The specified components need to work together as the tested or assessed doorset.

What Changes at Installation Stage?

A drawing can specify the correct rating and the finished installation can still fall short of the intended arrangement. The doorset has to be fitted in a way that corresponds with its supporting evidence and the manufacturer’s instructions.

Frame fixing, compatible hardware, glazing and seals all deserve attention. Gaps around the door leaf also need to follow the limits for the particular doorset rather than a measurement copied from another product.

Weight can make an FD60 installation more demanding where the chosen product uses a heavier leaf or frame. Hinges and closers still need to suit the doorset, and the surrounding construction needs to accommodate the specified installation detail.

Changing components also needs care. A different hinge, closer or piece of glazing may appear to serve the same purpose, but appearance alone does not show that it is covered by the doorset’s test evidence.

How Should You Choose Between FD30 and FD60?

Start with the required fire resistance for the opening, not with the door catalogue. Check the building’s fire strategy, the applicable Scottish building standards guidance and the performance required from the wall or compartment containing the door.

Then check whether smoke control is required. FD30 and FD30S are not interchangeable designations, just as FD60 and FD60S do not describe the same performance. Scottish fire safety guidance distinguishes the fire resistance period from the additional smoke control function.

Finally, make sure the specification covers the complete doorset. The rating, frame, seals, glazing, ironmongery and installation details need to describe an assembly that has suitable supporting evidence.

FD60 is not automatically a better choice than FD30. The right rating depends on the fire strategy, the construction around the opening and the level of protection required at that point in the building. Once that has been established, the frame, hardware, seals and installation details need to support the same level of fire performance.

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