Fire Door Packers: Where Do Hardwood Wedges and Plastic Packers Fit?
Use only packing materials permitted by the exact fire-door assembly’s installation evidence. “Hardwood” on a wedge listing or “door packer” on a tub is not proof of fire-door suitability.
Packers help position and support a frame; the fire door’s performance depends on the complete assembly. The leaf, frame, seals, hardware, wall opening and frame-to-wall sealing detail all need to work together. A general joinery product cannot establish that performance on its own.
What does a frame packer do?
A packer occupies a specified gap between the frame and supporting construction, helping maintain the intended alignment and support at the fixing. It is different from the operating clearance between the closed door leaf and the frame.
Do not use a frame screw to pull an unsupported frame across an arbitrary gap. For fire-door work, the installer must follow the approved fixing and packing arrangement rather than borrowing a detail from an ordinary internal door.
Hardwood wedge, flat packer or fire-stopping material?
| Item | Its general role | Fire-door buying check |
|---|---|---|
| Tapered hardwood wedge | Adjustable positioning or packing in suitable joinery work | Is this exact material, density, shape and position permitted, and may it remain? |
| Flat plastic packer | Packing at a stated thickness in a suitable frame arrangement | Is this product or material included in the assembly’s supporting evidence? |
| Specified fire-stopping material | Sealing the frame-to-wall gap in a proven detail | Match the gap, substrates, backing, product and application depth |
| A doorstop wedge under the leaf | Holding a door open | Do not wedge a fire door open; it must be able to close as intended |
Can hardwood wedges be used for fire-door frames?
Only where the relevant installation instructions and evidence allow that packing detail. The wood species or density, dimensions, location and whether packing remains after installation may be specified. A generic description does not answer those questions.
Our 95 x 19mm hardwood wedges are general joinery wedges. They have a tapered form, which differs from a flat packer of constant thickness. We are not presenting them here as universally approved fire-door packers. Confirm the exact doorset requirements before selecting permanent packing.
Can plastic packers be used?
There is no useful blanket answer based only on a door being FD30 or FD60. The permitted materials depend on the tested assembly and its installation instructions. Do not convert one manufacturer’s permitted plastic or timber detail into a rule for every fire door.
Our 1–6mm assorted flat plastic packers provide measured packing thicknesses for suitable general applications. Their colour or thickness does not establish fire performance. If the fire-door specification requires an identified tested packer, source that component.
Check the frame-to-wall fire stop as well
The BWF Fire Door Alliance installation guidance directs installers to the manufacturer’s instructions. Its best-practice guide calls for packers with proven performance in an accredited fire-door test and an appropriate proven frame-to-wall sealing detail.
A cartridge marked fire rated is not approval to fill every gap to any depth. Obtain the detail for the actual frame and wall substrates, gap size, backing and sealant. The packing and fire-stopping arrangement need to be considered together.
What should I ask for before buying?
- The door or doorset reference and its installation instructions.
- The permitted frame construction and wall opening detail.
- Packer material, dimensions, positions and any removal or trimming requirements.
- The specified fixings and frame-to-wall sealing system.
- The installer’s inspection and completion requirements.
Have fire-door installation and repairs carried out by a competent person. London Fire Brigade’s guidance also stresses that fire doors must close fully and should not be wedged open.
For ordinary joinery, our wooden wedges versus plastic packers guide compares the formats. Browse shims, packers and wedges for general applications, keeping the fire-door approval check separate.
