ASTM Issues New Standard for Fly Ash Brick

Words: Bronzella Cleveland

ASTM International has published ASTM C1790-14, Standard Specification for Fly Ash Facing Brick. ASTM standards are a crucial tool for architects, engineers, specifiers, installers, and project owners, providing assurance that products meet established, consensus-based criteria for performance and quality.

CalStar Products, which manufactures a range of brick and masonry products using up to 37 percent fly ash, is the first manufacturer to offer products that meet the new standard.

Development of C1790 involved an exacting, consensus-based process within ASTM’s established hierarchy of committees, subcommittees, and task groups. More than 300 members of ASTM Committee C15 Manufactured Masonry Units were invited to comment on the standard. Final passage required approval (or abstention) from approximately 200 voting members on the committee, representing masonry, equipment, and material manufacturers, trade associations, mason contractors, general users, and other industry stakeholders.

The resulting specification covers fly ash brick intended for use in masonry, in both structural and facing applications.

“The development of an ASTM standard requires several years of work and an immense commitment from key players within a building product category; as such, the creation of C1790 further affirms the importance and relevance of the fly ash brick category,” says CalStar CEO Joel Rood. “CalStar’s leadership in developing the category and driving the standard creation has both fostered acceptance for this growing technology and opened the door for future applications that combine performance with resource conservation through use of fly ash.”

The standard also provides additional corroboration of performance for CalStar’s bricks. “As the pioneer in fly ash brick technology, CalStar has subjected its masonry products to significant and extensive testing, often above and beyond industry counterparts,” says Julie Rapoport, Ph.D., P.E., LEED AP, CalStar’s vice president of engineering. “With the creation of ASTM C1790, product specifiers and end users have additional validation of the product category, in a format that is fully understood and accepted by all parties within a project team.”

Masonry Mortar: The Right Type for the Job
May 2025

When it comes to masonry construction, mortar is much more than “glue” that holds everything together — it’s a critical component of wall performance, longevity, and aesthetics. It can “make it or break it”. Whether you’re laying a foundation CMU wall or

MASONRY STRONG Podcast, Episode 20 Recap: Mark Kemp, Superior Masonry
May 2025

How It’s Made: Clay Thin Brick
May 2025

Clay thin brick is a versatile alternative to traditional full brick. It comes in numerous colors and styles and offers something for every design preference. Thanks to the lighter weight, it is designed to reach spaces full brick cannot. From floors to c

Bonding with Masonry 2025: Q1
May 2025

This issue’s questions come from an Architect and a Mason Contractor. What questions do you have? Send them to info@masonrymagazine.com, attention Technical Talk. Q. An Architect asks how to create a narrow masonry pier between openings. Is there a min