GREAT STUFF™ Fireblock Insulating Foam Sealant

GREAT STUFF™ Fireblock

Now with the SMART DISPENSER™!


Impedes The Spread Of Flames And Smoke

GREAT STUFF™ Fireblock is specially formulated to impede the spread of flames and smoke through service penetrations – helping to slow the spread of these destructive elements during a fire.



  • Impedes the spread fire and smoke1
  • Bright orange in color for easy code identification
  • UL Classified
  • ICC-ES Evaluated ESR-1961
  • Seals electrical wires running through wall studs.
  • Creates an airtight, water-resistant seal.
  • Closes gaps and cracks, increasing the comfort and energy efficiency of your home.

It's easy to use because it's:

  • All-direction dispensing.
  • Tack-free in 5-15 minutes, trims in one hour2
  • Rigid after 8 hours of curing.
  • Adheres to most building materials.

1Intended for use in residential application to maintain the continuity of an approved fire block material. Not to be used in firestop applications.
270 ± 5°F and 50 ± 5 % RH, 1-inch bead diameter, 6-inch length. The cure rate is dependent on temperature, humidity, and size of the foam bead.



No drips, less mess - foam stops where you stop.
Reusable for up to 30 days - use again and again.
Precise, greater control.


Down To The Details Of Great Stuff™ Fireblock


Air-Seal Audit Checklist


How To Use Great Stuff™ Fireblock

Read all instructions and safe handling information before you start. GREAT STUFF™ products should not to be used for filling closed cavities or voids such as behind walls and under tub surrounds.


Got a lot of GREAT STUFF™ projects on your to-do list?

Check Out Our Great Stuff™ Line Up

Great Stuff™ Insulating Foam Sealants Safe Handling

For warnings and precautions, disposal information and more, download GREAT STUFF™ Consumer Safety Information or view our safe handling videos.

If you need assistance, contact us. We're always here to help you through any project.

Download User Safety Information Download Consumer Safety Information Renseignements Sur La Sécurité Du Produit Great Stuffmc Pour Le Consommateur Sur La Sécurité Du Produit Mousse D'étanchéité Isolante Great Stuff Promc

What Project Do You Want To Start?

GREAT STUFF™ Fireblock works in a broad range of applications.

Sealing HVAC ducts and pipe penetrations

Watch our video to learn how to use Great Stuff spray foam insulation to seal around HVAC ductwork and penetrations.

Sealing HVAC ducts and pipe penetrations
Read more
Sealing around electrical and cable lines

Did you know our Great Stuff Spray Foam Insulation will stop air leaks through your electrical panelboard and help you save energy?

Sealing around electrical and cable lines
Read more
Air Sealing around electrical boxes and outlets

View our informative video to learn how to insulate and seal gaps around electrical wiring using expanding spray foam.

Air Sealing around electrical boxes and outlets
Read more

Ready to go shopping?

See where you can buy GREAT STUFF™ and GREAT STUFF PRO™ in your neighborhood.

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