Question 1

When is an FD30 fire door required in a UK dwelling?

Accepted Answer

In a standard 2-storey dwellinghouse (top floor up to 4.5m above ground), fire doors to habitable rooms are generally NOT required under Approved Document B Volume 1 — instead each habitable room (except the kitchen) must have an escape window or external door, or direct access to the protected stairway. FD30 fire doors to habitable rooms opening onto the protected stairway/landing are required at 3 or more storeys (any floor more than 4.5m above ground, including a loft conversion that adds a 3rd storey), and in HMOs all habitable-room doors to common areas must be FD30S. The one fire door needed in a typical 2-storey house is the integral garage door, which must be FD30S (with smoke seals). FD20 (E20) still appears in AD B Table C1 for some dwelling doors, but FD30 is the standard product fitted and the rating building control normally accepts.

Question 2

What is the difference between FD30 and FD30S fire doors?

Accepted Answer

FD30 provides 30 minutes of fire resistance (integrity). FD30S adds an "S" for smoke seal, meaning the door includes cold smoke seals that prevent smoke passage at ambient temperatures. Flat entrance doors, HMO room doors, and doors to protected stairways all require the "S" designation with combined intumescent and smoke seals. The smoke seal is typically a nylon brush or blade type fitted within the intumescent strip.

Question 3

What ironmongery is needed on a fire door?

Accepted Answer

All fire door ironmongery must be CE-marked and fire-tested as part of a door assembly. Requirements include: 3 ball-bearing hinges to BS EN 1935 (grade 12, 13 or 14 acceptable where a self-closer is fitted — grade 13 is the common spec), a self-closing device (BS EN 1154), intumescent strips in the frame or door edge, a fire-rated lock or latch (BS EN 12209), and signage (Fire Door Keep Shut to BS EN ISO 7010 / BS 5499-4). Letterplates are generally not permitted unless fire-rated to BS EN 13724. All items must be fitted per the door manufacturer's installation instructions.

Question 4

Do fire doors need intumescent strips?

Accepted Answer

Yes, all fire doors require intumescent strips to seal the gap between door and frame during a fire. The intumescent material expands when heated to approximately 200 degrees C, sealing gaps and preventing fire and smoke passage. Standard sizes are 10mm x 4mm for FD30 doors and 15mm x 4mm for FD60 doors. They are fitted into a groove in either the door edge or the frame rebate. Some locations also require a combined intumescent and cold smoke seal.

Question 5

Can I have a glazed panel in a fire door?

Accepted Answer

Yes, but the glazing must be fire-rated to match the door rating. For FD30 doors, Georgian wired glass (6mm) or proprietary fire-rated glass such as Pyran S or Pyroguard can be used. The maximum glazed area is typically 0.5 square metres unless the manufacturer has test evidence for larger panes. The glazing beads must incorporate intumescent backing strips. All glazed fire doors must be tested as complete assemblies to BS 476-22 or BS EN 1634-1.

Fire Door Specification Calculator — FD30/FD60 Rating per Part B

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