Example Data Table
These sample entries demonstrate typical round penetrations and joint beads.
| Item | Count | Hole Diameter | Pipe/Cable OD | Sealant Depth | Joint Length | Bead (W×D) |
|---|---|---|---|---|---|---|
| Electrical conduit | 8 | 90 mm | 63 mm | 25 mm | — | — |
| Data cable bundle | 4 | 60 mm | 35 mm | 20 mm | — | — |
| Head-of-wall joint | — | — | — | — | 12 m | 20×20 mm |
| Perimeter joint | — | — | — | — | 18 m | 15×25 mm |
Formula Used
1) Round penetration (annular space)
- Annular area: A = (π/4) × (Dhole2 − Ditem2)
- Volume for penetrations: Vround = A × t × N
- Where t is sealant depth, and N is count.
2) Linear joint (bead approximation)
- Bead cross-section (approx.): Abead = w × d
- Joint volume: Vjoint = Abead × L
- Where L is joint length, w width, d depth.
3) Total with waste
- Base volume: Vbase = Vround + Vjoint
- Final volume: V = Vbase × (1 + Waste%/100)
- Cartridges: C = ceil(VmL / CartridgemL)
How to Use This Calculator
- Select your measurement units for diameters and depths.
- Enable round penetrations and enter hole, item, and depth.
- Enable linear joints and provide length and bead sizes.
- Set waste factor, cartridge size, and optional density.
- Press Calculate to view results above the form.
Firestop Sealant Quantity Planning
1) Scope and typical applications
Firestop sealant restores fire and smoke resistance where services pass through rated walls and floors. It is also used at head-of-wall, perimeter, and control joints when the tested system requires a bead. This calculator covers both penetrations and linear joints to support takeoffs, purchasing, and crew planning.
2) Key inputs and field measurements
Count penetrations, measure hole or sleeve diameter, then measure pipe or cable outside diameter. Record the required sealant depth from the listed system, because depth drives volume. For joints, measure total length and the required bead width and depth from the detail. You may enter diameters in millimeters or inches, and joint length in meters or feet; the tool normalizes units internally. When openings are irregular, measure the smallest effective diameter that matches the listing limits.
3) Penetrations: annular space filling
Penetration volume is calculated from annular area multiplied by sealant depth and count. Annular area equals the hole area minus the service area, producing a uniform ring quantity. If backing material is specified, only enter the sealant thickness above the backing.
4) Linear joints: bead-based estimating
Joint consumption uses bead area (width × depth) multiplied by joint length. The bead is approximated as a rectangle, which is appropriate for estimating and often conservative. Keep bead dimensions aligned with the tested assembly and the installer’s tooling method.
5) Procurement, waste, and quality control
Results convert volume to cartridges, apply waste, and optionally estimate weight using density. Use waste to cover nozzle losses, rework, and irregular voids. The joint section also provides an approximate coverage per cartridge, helping you stage materials by area. Document the system listing, backing type, and curing limits before ordering and installation. Store sealant within the manufacturer’s temperature range to protect workability and cure performance.
FAQs
1) Is this calculator a substitute for a tested firestop listing?
No. It estimates quantities for planning. Compliance depends on the listed system details, including annular space limits, backing requirements, sealant depth, substrate, and penetrating item type.
2) What sealant depth should I enter for penetrations?
Use the specified sealant thickness from the system listing. If a backing material is required, enter only the sealant depth above the backing, not the full wall or slab thickness.
3) How does the joint bead calculation work?
It multiplies bead width by bead depth to get area, then multiplies by joint length for volume. The bead is approximated as a rectangle for a practical field estimate.
4) Why does it round cartridges up?
Sealant is purchased as whole cartridges or sausages, so the calculator uses a round-up rule. This also helps avoid shortages caused by nozzle losses and small voids.
5) What waste factor is reasonable?
Many teams use 5–15% depending on crew experience, rework risk, and bead complexity. Increase waste if the work includes overhead applications, irregular openings, or frequent start/stop runs.
6) Can I use inches for diameters and depths?
Yes. Select “inch” for diameters and depths. Joint length can still be entered in meters or feet. Internally, everything is converted to millimeters for consistent volume calculations.
7) How do I estimate weight for transport and storage?
Enter the product density in g/mL from the datasheet. The calculator multiplies density by total mL to estimate mass, which helps with handling limits and site logistics.