STI Firestop WF300 Intumescent Firestop Caulk

Call for Price

  • Installer friendly, easily applies with standard caulking gun
  • Suitable for combustible and non-combustible penetrants
  • Tested for up to 3 Hours of fire exposure when tested to ASTM E814/UL1479
  • UL® GreenGuard Gold Certified

SKU: N/A Category: Tag:

WF300 Intumescent Firestop Caulk is a latex-based firestop caulk designed for residential wood frame construction. WF300 Caulk is tested for addressing penetrations through wood/frame construction such as wood stud walls and floor/ceiling assemblies. Under fire exposure, WF300 expands to up to four times its original volume.

Physical Properties

Density/Weight per Gallon10.2 lbs/gal (1.22 kg/L)
Solids Content by Weight81%
Solids Content by Volume77.6%
Flame Spread0*
Smoke Development20*
CoverageFor more information on product coverage see the following documents for Linear Joint & Penetration
pH7.4 to 8.4
In Service TemperatureLess than 185°F (85°C)
Storage Temperature40°F (4°C) to 95°F (35°C)
Application Temperature35°F (2°C) to 100°F (38°C)
STC Rating (ASTM E90-04/ASTM C919)61 (Relates to Specific Construction)
VOC Content53 g/L**
Expansion Begins350°F (176°C)
Average Volume Shrinkage (ASTM C1241)23.5%
Volume Expansion5x Free Expansion
Shelf Life From Date of Manufacture24 months

*Tested to ASTM E84 (UL723) at 14% surface coverage (modified test for sealants and caulks)

**Per SCAQMD Rule 1168 (EPA Method 24)


STI Firestop


10.1 oz Tube, 20 oz. Sausage, 5 Gallon Pail

© 2021 Cable and Connections Acquisition Company LLC. | 888-WIRE-682 (888-947-3682)