FF365 Fire Rated Sealant
UL Classified Intumescent Firestop Sealant - Up to 2-Hour Fire Protection
intumescent firestop sealant for use in a variety of UL through-penetration firestopping systems.
The Tenmat FF365 is a gun-grade, one-component intumescent fire rated sealant designed for through-penetration firestopping in fire-resistance-rated walls, floors, and ceilings. Classified by Underwriters Laboratories (UL) and tested to UL 1479 / ASTM E814, it delivers up to 2 hours of verified fire protection.
The FF365 works by expanding under heat. When a fire occurs, the intumescent compound swells to close the opening around cables, conduits, pipes, or blank penetrations, blocking both flame and smoke for up to 120 minutes.
It fits a standard 10 oz. caulking gun and requires no special tools. Water-based formula means easy cleanup, and it’s paintable once cured. Sag-resistant for overhead and vertical applications.
Why Specifiers and Contractors Choose the FF365 Fire Sealant
- UL Classified firestop sealant, tested to UL 1479 and ASTM E814, the two accepted standards under the IBC
- 2-hour F and T ratings available across multiple UL listed through-penetration systems
- Intumescent formula expands under heat to seal openings and stop flame and smoke spread
- Gun-grade application from a standard 10 oz. caulking gun, no specialist equipment required
- Water-based and paintable: easy application, water cleanup, compatible with finishing schedules
- Sag-resistant: suitable for overhead, vertical, and hard-to-reach penetrations
- Flexible when cured: route additional cables through the sealant without cutting or re-applying
- Works on blank openings, metal conduit, cables, wires, and mixed penetration types
- Compatible with FF260 Fire Protection Blocks and FF160 Fire Protection Plugs for combination assemblies
- Maintenance-free once applied in a listed system
In a fire, the intumescent material expands, closing the opening and preventing flame spread
FF365 Product Specifications
| Property | Value |
|---|---|
| Product type | Acrylic with halogen-free fire retardant additives, intumescent |
| Colour | Red |
| Chemistry | Water-based intumescent (acrylic/latex binder) |
| Bulk density | 1,300 – 1,450 kg/m³ |
| Transport / storage | 5 °C – 30 °C (41 °F – 86 °F) — dry, in original containersKeep from freezing |
| Application method | Gun-grade, standard 10 oz caulking gun |
| Application temperature | 10 °C – 30 °C (50 °F – 86 °F)Recommended: 20 °C – 25 °C (68 °F – 77 °F) |
| Content | 310 ml (10.48 fl oz) |
| VOC content | 20.2 – 23.3 g/L |
| Fire rating (max) | 2 hours / 120 min |
| Test standards | UL 1479 / ASTM E814 |
| UL classifications |
|
| Intumescent action | High-expansion — expands under heat to seal the annular space around penetrating items |
| Paintable | Yes, once cured |
| Cleanup | Water |
| Flexibility | Remains flexible after curing |
| Substrates | Concrete, masonry, drywall / gypsum board, steel |
| Penetration types | Blank openings, metal pipes, conduits, cables, wires, mixed penetrations |
| Assembly types | Floors, walls and ceilings |
| Maintenance | Maintenance-free when installed in a listed system |
| Environmental conditions | Dry rooms, indoors, above 0 °C (32 °F)Outdoor use permitted with additional silicone coating |
| Full technical data | See FF365 Information Sheet and SDS (Downloads section) |
Where to Use the FF365 Fire Sealant
The FF365 fire sealant is suited to a wide range of through-penetration applications in fire-resistance-rated assemblies. Below are the most common installation scenarios.
1. Cable and Wire Bundles Through Fire-Rated Walls
When multiple low-voltage, data, or electrical cables pass through a single opening in a fire-rated wall, the FF365 is applied around and into the bundle to close the annular space. The flexible, water-based formula works into irregular cable bundles where rigid products cannot. The flexible cure means additional cables can be added later without full re-application.
2. Metal Conduit Penetrations
Steel conduit is non-combustible but the annular gap around it still requires sealing in a rated assembly. The FF365 is gun-applied directly into the gap. Select the UL listed system that covers the conduit diameter and assembly type on your project.
3. Blank Openings and Unused Penetrations
Construction often leaves blank or partially filled openings that need to be closed before inspection. The FF365 can be applied directly to blank openings in walls or ceilings. For larger openings, use the FF365 in combination with the FF260 Fire Protection Block as backing material.
4. Hard-to-Reach and Irregular Penetrations
The sag-resistant formulation makes the FF365 reliable for overhead or angled applications. The gun-grade format allows precise placement in confined or awkward locations, including above ceiling tiles and inside wall cavities.
5. Small Membrane Penetrations
The FF365 is specifically rated for small membrane penetrations. This covers the typical penetration types found in multi-family residential, healthcare, data center, and other commercial construction where IBC fire-rated assembly requirements apply.
Common Sectors Where the FF365 Is Specified
- Multi-family residential: IBC through-penetration requirements in rated floor/ceiling and wall assemblies
- Healthcare and assisted living: strict fire compartmentalization in patient areas
- Education: schools and university buildings with fire-rated corridor walls and floor/ceiling assemblies
- Data centers: cable-dense environments with high through-penetration density
- Hospitality and commercial: hotels, offices, and retail buildings with rated construction
Code Compliance and Test Standards
Through-penetration firestopping is a code-mandated requirement in the United States. Selecting a product tested and classified under the correct standards is a prerequisite for inspection sign-off.
International Building Code (IBC): Section 714
IBC Section 714 governs through-penetration firestop systems in fire-resistance-rated assemblies. It requires that penetrations be protected by a tested and listed firestop system installed per the manufacturer’s instructions. The FF365 is part of UL listed through-penetration systems that satisfy IBC 714 requirements.
UL 1479 and ASTM E814
The FF365 is tested and classified to UL 1479 (Standard for Fire Tests of Through-Penetration Firestops), which is equivalent to ASTM E814. Both are accepted under the IBC. The test evaluates:
- F Rating: time in hours the assembly resists the passage of flame through the penetration
- T Rating: time in hours before the non-fire-side temperature exceeds 325 degrees F above ambient, required for floor penetrations in most IBC applications
FF365 systems provide up to 2-hour F and T ratings, meeting the minimum IBC requirement for floor and wall penetrations in most fire-resistance-rated construction types.
NFPA 101 Life Safety Code
NFPA 101 includes firestopping requirements for egress-related assemblies and occupancy separations. Products installed in systems tested to UL 1479 / ASTM E814 satisfy NFPA 101 firestopping requirements.
UL Classified Systems
The FF365 fire rated sealant is a component in seven published UL listed through-penetration firestop systems. Each system number defines the specific combination of assembly type, penetrating item, annular space, and sealant. Match the system number to your project assembly when specifying or installing.
How to Apply the FF365 Fire Sealant
Installation follows the specific UL listed system that covers your project assembly. The general process is:
- Clean the component opening. Surfaces on which the Fire Protection Sealant FF365 is applied should be free of dirt, oil, wax and grease.
- Backfill material, consisting of mineral wool, must be used. For secure installation use pre-cut mineral wool batt insulation (4 pcf/ 64 kg/m3) firmly packed into annulus as a permanent form. It must be ensured that the minimum fill depth of the Fire Protection Sealant FF65 can be applied from both surfaces of the wall or top surface of the floor.
- Hold the cartridge cautiously, cut off the tip with a sharp knife, and screw on the nozzle. The nozzle can be shortened as needed.
- Insert the cartridge into the intended dispensing gun.
- Fire Protection Sealant FF365 must be introduced uniformly into the opening from back to front or bottom to top with a min. thickness of approx. 1/2” (13mm).
- Smoothing can be executed with a moistened smoothing trowel or brush.
Always install per the published UL system instructions. Deviating from the listed system voids the classification.
Product Details
The TENMAT FF365 Fire Protection Sealant is a red, one-component, gun-grade, intumescent firestop sealant for use in a variety of UL through-penetration firestopping systems.
TENMAT Fire Protection Sealants help properly fire rate small membrane penetrations in walls and ceilings and control the spread of flames and smoke in case of a fire for up to 2 hours.
The FF365 is suitable for irregular, hard-to-access, and small penetrations and can be used in combination with other TENMAT products such as the FF260 Fire Protection Blocks and the FF160 Fire Protection Plugs.
Recommended applications include: Blank openings, metal pipes, conduits, wires and mixed penetrations in solid floors and ceilings.
The FF365 Fire Protection Sealants fits into standard size 10 oz. caulking guns and can easily be applied within seconds.
The high expansion and insulating properties of the material ensures that both, flame spread and smoke, are stopped for 120 minutes. For a full list of our UL listed through-penetration firestopping systems, please visit the DOWNLOADS section.
Content 10.48 fl. oz
Completing Your Firestopping System
The FF365 fire sealant works as a standalone solution in many applications, and as part of a combined system with other TENMAT passive fire protection products.
A pre-formed intumescent block for larger penetration openings. Used as backing material for the FF365 sealant in cable tray and large opening applications.
A single-component intumescent firestop foam for irregular or larger through-penetrations where a gun-applied sealant is less practical.
A pre-formed intumescent plug for single cable and conduit penetrations in walls and floors. Often used alongside the FF365 in combination firestop assemblies.
View the full firestop foams, sealants and blocks range for the complete TENMAT through-penetration firestopping product family.
