FireEG graphite sponge is a low-density, compressible intumescent foam material for fireproof sealing and thermal insulation of large penetrations — including cable trays, ventilation ducts, and multi-service openings where conventional firestop products are impractical. It compresses for easy installation and expands when heated above 200°C, forming a dense carbonaceous char that blocks flame, smoke, and heat transfer.
Technical Specifications
| Parameter | Value |
|---|---|
| Base Material | Expandable graphite (carbon-based) |
| Density | 100 kg/m³ |
| Free Expansion | Volume ≥1x (450°C, 15 min) |
| Activation Temperature | 200°C (392°F) |
| Max Width | ≤1,000mm |
| Compressibility | High — hand-compressible for installation |
| Post-activation form | Dense carbonaceous char |
| Halogen Content | None |
Why Graphite Foam for Large Openings?
Conventional firestop products — intumescent strips, sealants, and rigid boards — are engineered for defined, fixed-geometry penetrations. Large, irregular openings present a different challenge:
The problem with large cable tray penetrations: Cable trays carrying multiple cable bundles through a fire-rated floor or wall create large, partially-filled openings. The cable fill changes over the facility lifecycle as cables are added or removed. Rigid firestop systems become obsolete every time the cable configuration changes.
How graphite sponge addresses this:
FireEG graphite sponge is cut to fit the opening — including around existing cables — and compressed into place by hand. No mixing, no curing, no specialist tools. When a fire occurs, the material expands from 200°C to form a carbonaceous char that seals the void completely, including around individual cable jackets.
The low density (100 kg/m³) means large volumes of material can be handled and installed easily, while the compressible structure conforms to irregular shapes and cable arrangements that pre-formed blocks cannot accommodate.
Typical Applications
✓ Cable tray penetrations through fire-rated floors and walls
✓ Large blank openings (unused penetrations awaiting future services)
✓ Ventilation duct and air handling unit penetration sealing
✓ Multi-cable and mixed-service penetrations
✓ Backing material in large opening firestop systems
✓ Heat insulation for industrial equipment and pipeline systems
✓ Thermal gap filler in high-temperature industrial assemblies
Installation Advantages
No tools required
Graphite sponge is cut with a knife or scissors and compressed by hand into the penetration. No mixing, no dispensing equipment, no curing time — suitable for retrofit installation by site personnel without specialist firestop training (subject to AHJ requirements).
Re-enterable
Unlike cured sealants or hardened mortars, graphite sponge can be removed and replaced when cables need to be added, changed, or removed. The firestop integrity is restored by replacing the material — no demolition or re-certification of the surrounding structure required.
Adaptable to irregular geometry
The compressible structure fills around cables, conduits, and other penetrants of varying sizes and cross-sections — including configurations that pre-formed firestop blocks cannot accommodate.
Frequently Asked Questions
Q: How does graphite sponge differ from mineral wool firestop?
Graphite sponge is actively intumescent — it expands when heated above 200°C to form a carbonaceous char that seals the opening. Mineral wool is a passive insulator that does not expand; it relies on high-density packing to resist flame penetration. Graphite sponge provides active sealing action and is typically lower density (easier to handle) than mineral wool firestop packs.
Q: What is the maximum opening size suitable for graphite sponge?
Graphite sponge is suitable for large openings including cable tray penetrations. Please contact us with your opening dimensions for application guidance.
Q: Can graphite sponge be used alongside intumescent sealant?
Yes. For large openings, graphite sponge is often used as the primary fill material, with intumescent sealant applied around the perimeter and to seal gaps between the sponge and the substrate. This combination is typical in professional firestop practice.
Q: Is graphite sponge halogen-free?
Yes. As a carbon-based material, expandable graphite contains no halogens. No HCl or HBr is released during activation.
Q: What is the shelf life?
Graphite sponge is stable at ambient temperatures and does not degrade under normal dry storage conditions. Protect from moisture and prolonged UV exposure.
Related Products:
[→ Intumescent Strips – for smaller defined penetrations]
[→ FEG-1000E Acrylic Sealant – perimeter sealing complement]