Contact Us Now

Call Us Today at:
(800) 638-3160

Firestop Collars 101


What you need to know about intumescent firestop collars and wrap strips.

In the firestop industry, we have a saying that if a wrap strip or firestop collar can’t do it, nothing can. Although our Firestop-814+ Intumescent Sealant is UL tested for a variety of firestopping applications for up to 3 hours, when it comes to “hard pass” firestopping scenarios, wrap strips, and firestop collars are the last line of defense. They possess the most significant expansion and fire resistance in our line of firestopping products.


Wrap Strips are flexible strips of highly intumescent firestop material used primarily for plastic and insulated pipe applications. When exposed to heat, wrap strips drastically expand to seal the penetration as the combustible plastic pipe or pipe insulation melt away. As the strip expands, it hardens to form a protective char that acts as a barrier to prevent the passage of flame, smoke, and gasses from one building compartment to another.

Our wrap strips come on a 1″ wide x ¼” thick x 144″ roll and a 2″ wide x ¼” thick x 144″ roll. They are easy to install by wrapping the required number of strips around the penetrating item and pushing them into the annular space.

Intumescent Firestopping Wrap Strips


Intumescent firestop collars (also known as pipe collars) are used for areas with insufficient annular space to fit a wrap strip. Firestop collars are prefabricated metal devices that house a precut section of wrap strip, allowing the installer to wrap the collar around the pipe and fasten it to the substrate. The easy-lock mechanism of our firestop collars ensures a simple, quick, and secure installation.

Firestop Collar

Both wrap strips and firestop collars are typically used for penetrations using PVC, CPVC, ABS, PVC foam core, ABS foam core, FRPP, PEX pipe, and electrical cables. Both are UL Classified for open and closed pipe systems and are used most often for pipes 3 inches or greater in diameter.

Though our Firestop-814+ Intumescent Firestop Sealant has UL testing for pipes up to 2 inches in diameter without the use of a collar, many inspectors require a firestop collar on 1.5-inch and 2-inch pipes. As with extensions of our published firestop data, we recommend checking with the AHJ before installation.