Installing a fire door lining correctly is essential for ensuring the fire door performs as intended. Even a certified FD30 or FD60 fire door can fail if the lining is fitted incorrectly, out of tolerance, or missing the correct intumescent seals.

This guide explains how to install a fire door lining properly, what to check, and how to avoid the most common mistakes seen on UK building sites.

At Timber Mouldings Direct, we supply a full range of FD30 and FD60 fire door linings, available in standard sizes, wider options, and custom sizes on request. Our linings are trusted by joiners, builders and developers across the UK.

1. Check the Fire Rating Requirements

Before installation begins, confirm whether the opening requires an FD30 or FD60 lining. You can browse both options here: 👉 Fire door lining kits

2. Prepare the Opening

Ensure the structural opening is plumb, level and square. If you need matching mouldings for the surrounding area, see our skirting and architrave (https://www.timbermouldingsdirect.co.uk/collections/skirting-board-and-architraves) range.

3. Assemble the Fire Door Lining

Assemble the lining on a flat surface, ensuring joints are tight and the frame is square. If your kit includes intumescent grooves, ensure they are clean before fitting seals.

4. Position the Lining in the Opening

Use packers to position the lining correctly. If you require a non‑standard size, we can manufacture custom fire door linings to suit unique wall thicknesses.

5. Fix the Lining Securely

Fix through the jambs into the structure using appropriate fire‑rated fixings. Avoid over‑tightening to prevent twisting.

6. Check Clearances and Tolerances

Fire doors require specific gaps to perform correctly:

• 2–4mm between door and frame

• 3mm at the head

• Under‑door gap per manufacturer’s instructions

Incorrect gaps are one of the most common reasons fire doors fail inspections.

7. Fit the Door Stops

Once the lining is fixed, fit the door stops. If you need replacements or additional components, see our timber door stops.

8. Install the Fire Door Leaf

Hang the fire door using fire‑rated hinges and screws. If you require a fully certified fire door, our sister company Timbermate UK manufactures complete FD30 and FD60 fire‑rated doorsets: 👉 www.timbermateuk.co.uk

9. Fit Intumescent & Smoke Seals

Install the correct intumescent or combined smoke seals as specified. These must be continuous around the frame.

10. Final Checks Before Sign‑Off

Before inspection, check:

• Gaps are within tolerance

• Seals are continuous

• Hinges are fire‑rated

• Door closes fully

• Lining is secure and undamaged

A correctly installed lining ensures the fire door performs as a complete, compliant system.

Certified Fire Doors & Custom Linings Available

Although our fire door linings are manufactured to high standards, fire certification applies to the complete doorset — not the lining alone.

If you require a fully certified FD30 or FD60 fire door, our sister company Timbermate UK can manufacture complete fire‑rated doorsets to the correct specification.

We can also manufacture custom‑size fire door linings for non‑standard wall thicknesses or unique project requirements.

Order Your Fire Door Lining Today

Explore our full range of FD30 and FD60 fire door linings here: 👉 Fire Door Lining Kits

If you need help choosing the right kit or require a bespoke size, our team is always happy to assist.