KILARGO FDBU20 RETROFIT INTUMESCENT FIRE DOOR BOTTOM SEALS
KILARGO FDBU20 RETROFIT INTUMESCENT FIRE DOOR BOTTOM SEALS
The Kilargo FDBU20 is a retrofit intumescent fire door bottom seal used to upgrade existing fire doors where the bottom gap exceeds the 10 mm allowed by AS 1905.1 – sealing gaps up to 20 mm under nominal 35 mm and 45 mm proprietary fire doors. Non-compliant fire doors are salvaged without removing, rebuilding or replacing the door.
Key Features
What It's Used For
When a fire door inspection finds the bottom gap over 10mm – from floor wear, re-carpeting or door trimming – the FDBU20 restores compliance in one screw-on application. Standard kit for fire door maintenance contractors and body corporates.
Kilargo 4000 Series threshold plates may be incorporated for aesthetics and disability compliance; gaps beyond 20mm step up to the FDBU60 series. Check approvals with your door manufacturer.
Specifications
| Type | Retrofit intumescent fire door bottom upgrade seal |
| Gap capability | Up to 20mm under nom. 35mm & 45mm proprietary fire doors |
| Materials | Anodised aluminium, silicone gasket, integral intumescent seals |
| Fixing | Pre-drilled slotted holes & screws (door stays hung) |
| Finish | Clear anodised (silver) with grey gaskets |
| Available sizes | 820mm, 920mm, 1220mm |
| MPN | FDBU20 |
Compliance & What It Means
Fire and smoke approvals apply to tested, proprietary door assemblies. Always confirm suitability for your specific door type and required rating with your fire door manufacturer or building certifier.
When do I need an FDBU20?
When the gap under a fire door exceeds the 10mm allowed by AS 1905.1 - a common inspection failure. The FDBU20 seals gaps up to 20mm; for gaps up to 60mm, use the Kilargo FDBU60-35 or FDBU60-45.
Does the door have to come off its hinges?
No - the FDBU20 screws onto the bottom of the door leaf through pre-drilled slotted holes with the door in place.
How does an intumescent fire seal work?
The core is an intumescent material that stays inert at normal temperatures. In a fire, the heat makes it expand to many times its original volume, packing the gap between door and frame with an insulating char that blocks flames, heat and hot toxic gases - preserving the doorset's fire rating for its tested duration (up to 2 hours).
Which fire doors is the FDBU20 approved for?
It is fully tested to AS 1530.4 for up to 2 hours on proprietary fire door assemblies in accordance with AS 1905.1. Approvals are specific to tested door types - always confirm with your fire door manufacturer or certifier that the seal is covered for your doorset and required rating (FRL).
What is the handling time for this item?
This is a non-stocked, specialty architectural item ordered directly from the Kilargo factory. Allow a standard handling time of 5–8 business days after cleared payment before dispatch. If your project needs express turnaround, call Prime Hardware on 1800 329 028 to confirm current factory lead times.
I'm not sure this is the right seal for my door — can I get help?
Yes. Door sealing depends on your door type, the gap sizes and what you need to seal against (fire, smoke, sound, weather or drafts). Call Prime Hardware on 1800 329 028 with your door details and gap measurements and we'll confirm the right Kilargo seal, size and finish before you order.
