About Risi Stone

Risi Stone Inc. is the original inventor and pioneer of the Segmental Retaining Wall System. The beginnings of this phenomenal success story are rooted in the late 1960s, when brothers Angelo and Tony Risi developed and patented the original PisaStone® SRW System. The PisaStone block was manufactured in wet-cast molds and featured an attractive split concrete face. The system was simple, yet effective: high strength, solid concrete blocks that interlocked with a continuous tongue and groove to form a flexible, structurally stable retaining wall system. As the system was installed dry-stacked without the requirement of mortar, it was considered to be structurally flexible, and as a result, did not require the conventional 1.2m foundation depth that is common within Canada for frost protection.

In the early 1970s, the Risi brothers purchased their uncle’s pre-cast patio stone business just north of Toronto, Canada, in the small town of Richmond Hill. By the late 1970’s, they invested in a larger plant in nearby Gormley, and used a small board machine previously used for concrete paving stones, beginning the shift to dry-cast production on concrete machinery. They also set their focus to improving upon the original concept with the flagship Pisa2® SRW System.

Within a few short years, the PisaStone and Pisa2 SRW systems had become an enormous success with local contractors and homeowners alike, signaling the birth of Risi Stone Retaining Wall Systems.

Over the next two decades, Risi Stone developed a wide range of unique SRW Systems, many of them being industry firsts. Moving into the “Engineered Walls” market, Risi Stone was the first to introduce massive, machine placed systems, such as SienaStone®, Durahold®, Durahold2®, and SonomaStone®. With weights of up to 1750 lbs per block, these heavy-duty systems met the growing needs of the Civil Engineering community and opened up an entirely new market segment. These innovations lead to product market expansion and Licensing Agreements being established with other concrete manufacturers, the first being Barkman Concrete in 1982.

In 1995, Risi Stone transitioned from being a manufacturing entity, to solely a Licensing Company with the sale of the Gormley Plant to Unilock Ltd. Unilock continued manufacturing the Risi Stone line of SRW products under a licensing agreement, as these products were a natural addition to their thriving paving stone business. Since that time, Unilock has expanded throughout Ontario and the U.S. to become the premier hardscapes supplier in the industry.

Risi Stone has continued to license their line of Wall Systems to leading concrete producers across Canada, the US, and Internationally. The Risi Stone group of Licensees have enjoyed tremendous growth over the years, with many of the earliest adopters still going strong after more than three decades of proven success.

Foregoing the production side of the industry, Risi Stone has since repositioned itself as a support system for Licensees, Engineers, Architects, Landscape Architects and Designers, specializing in both the marketing and engineering aspects of the business.

Today, Risi Stone’s long-time culture of innovation and investment in R&D continues to keep them at the forefront of the industry.