Manufacturer RectorSeal Fire Stopping Products
SKU: 350i
Metacaulk 350i Intumescent Firestop Sealant

Metacaulk® 350i is an intumescent, water-based, non-sag caulking grade sealant that is easy to apply and is great for retrofits. It cures to an elastomeric seal that is suitable where dynamic movement is expected. In the event of a fire, Metacaulk® 350i will prevent the spread of flames, smoke, hot gases and water through joint openings and through-penetrations. Metacaulk® 350i systems are rated for 1, 2 and 3 hours in accordance with the ASTM E814 (UL 1479), UL 2079 and ULC-S115-95 test standards.


  • Top of the wall Construction Joints
  • Deflection Track Wall Systems
  • Up to 2" PVC/CPVC (Open)
  • Cross-linked Polyethylene (PEX) tubing
  • Steel, Copper, Cast Iron and EMT Pipe
  • Flexible Conduit
  • Fiberglass Insulated Pipe
  • Armaflex Insulated Pipe
  • Telephone, Communications and Power Cables
  • HVAC Ductwork

Metacaulk® 350i Features

  • Highly Intumescent; expands when exposed to fire
  • Water Based
  • Excellent Freeze-Thaw
  • Flexible Set
  • Paintable
  • VOC Compliant
  • Safe and Easy to Use
  • Protected against mold and growth
  • Sound Transmission Class (STC) rating 53*

*Tested in a UL 411 wall assembly/section to ASTM E90. 


Metacaulk® 350i | Product Information

Product Code Size Quantity Per Case
10.3 oz Cartridge
20.2 oz Sausage Pack
5 Gallon


Additional Product Literature
Data Sheet