Question 1

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

Accepted Answer

In dwellings of 2 or more storeys, fire doors are required between habitable rooms and the protected hallway/landing. All fire doors in UK dwellings are FD30 (30-minute, self-closing) minimum — FD20 is no longer a recognised UK rating. 3+ storey dwellings and loft conversions also require FD30. Integral garages always need FD30S doors (with smoke seals). In HMOs, all habitable room doors to common areas must be FD30S. These requirements come from Approved Document B, Volume 1.

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 x fire-rated hinges (BS EN 1935, grade 13), 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. 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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