Fire Rated

The use of “Underwriters Laboratories” Fire Rated Concrete Masonry Units is a necessity in all fire rated assemblies. Because there is virtually no difference in appearance between a standard CMU and a “Fire Rated UL CMU” Westbrook Block provides a specially marked CMU with a “Frog” on the end of each Underwriters Laboratories Fire Rated CMU. In the event the design professional, building committee, or local governing authority requires further assurance that the fire walls are indeed Underwriters Laboratories Fire Rated CMU’s, individual Fire Rated CMU’s can be marked with the “UL” logo. Furthermore, a UL Certificate is delivered to the job site and made available to any local building officials.

*Underwriters Laboratories Inc. (UL) is an independent, not-for-profit product safety testing and certification organization. UL has tested products for public safety for over a century. Each year more than 17 billion UL Marks are applied to products worldwide.

UL is not affiliated with Westbrook Block and does not endorse the Web site.


UL Design Numbers

u901 x902 u904 u905 u906 u910 u912 u913 u914


Fire Rated Specifiation

WCB Fire Rated Specification