How to Install an FD30 or FD60 Fire Door-set

Practical Guide #5

For: Joiners, installers, apprentices, and contractors fitting certified fire doors in new builds or refurbs.

Why Fire Door Installation Isn’t Just Another Door Job

Installing a fire doorset isn’t like fitting a standard internal door. If you get it wrong — even by a few millimetres — you can invalidate the fire certification and compromise the compartmentation. The gap, the fixings, the seals, the hardware — everything must match the tested specification.

This guide lays out the process clearly, helping you get the install right the first time.

Step-by-Step: Installing a Fire Doorset

1. Preparation & Verification

Before you touch a tool:

• Confirm certification of the doorset — leaf, frame, and hardware

• Check you have the correct leaf size, handing, rating (FD30, FD60), and matching frame

• Inspect the frame and leaf for damage, warping, or defects

• Review the manufacturer’s installation instructions — no two tested systems are identical

• Ensure the opening in the wall is suitable: plumb, level, and within tolerances

2. Frame Installation

• Mark your frame position clearly on the wall or floor

• Position the frame in the opening with temporary packers or wedges

• Use fire-rated packers (hardwood, mineral board, or graphite-based if specified)

• Fix the frame with approved fire-rated fixings (screws or bolts)

  • Usually 100mm from the top and bottom, then every 600mm

• Check diagonals and ensure the frame is square

• Gap between wall and frame should be between 5–10mm and consistent

Important: Do not use foam unless the manufacturer’s data sheet specifically allows it and gives a tested detail.

3. Seal the Frame-to-Wall Gap

This is one of the most commonly failed inspection points.

• Use only tested fire-stopping materials — e.g., rock wool + fire mastic, intumescent mastic, or graphite-based sealant

• Follow the door-set manufacturer’s guidance

• Label the frame with installer's name, date, and details if required

4. Hang the Door Leaf

• Mark hinge positions using the template or from the manufacturer’s guidance

• Rout mortices for hinges (typically 3 for FD30, possibly 4 for FD60 or heavier doors)

• Fit CE/UKCA-marked steel hinges with intumescent pads behind (if required)

• Carefully hang the leaf and check for the correct gaps:

  • 2–4mm gap between leaf and frame on all sides

  • Under-door gap:

    • Max 8mm for standard doors

    • Max 3mm if smoke seals are fitted

Check that the door opens freely, self-closes fully, and latches securely.

5. Install Seals and Ironmongery

• Fit intumescent seals (and smoke seals if required) either in the leaf or frame as specified

• Seal must be continuous around the perimeter — no gaps, tears, or short cuts

• Fit only approved hardware:

  • Fire-rated locks/latches

  • Fire-rated closers

  • Handles, signage, door viewers, etc. (if allowed)

• Use intumescent protection kits for locks/latches and hinges, where required

• Fix ironmongery with the correct screws — often steel or specified in the cert

6. Final Checks

Before sign-off:

• Test the closer: the door must fully close and latch without slamming

• Check gaps again with a feeler gauge

• Verify seals are intact and continuous

• Ensure hinges and hardware are firm and flush

• Ensure door leaf is not binding, dragging, or catching

Common Mistakes to Avoid

• Over-packing the frame, causing distortion

• Using expanding foam when not specified

• Relying on “standard joinery” techniques instead of following the test evidence

• Ignoring intumescent pad requirements under hinges/latches

• Cutting seals to fit around hardware — they must be continuous

• Hanging the door before fully fire-stopping the frame

• Using uncertified ironmongery — invalidates the door

Pro Tip

Photograph the install as you go — especially packers, fixings, fire stopping, and the labels. It protects you later and makes inspection easier.