Clay as a Sustainable Raw Material for High Quality and Durable Pavers

Composed of very fine mineral particles and formed through the weathering and erosion of rocks over long periods of time, clay has properties that make it useful for a wide range of applications. When wet, it becomes extremely malleable and plastic, and can be molded into different shapes. When dry, it is hard and rigid, and is widely used for construction and ceramics. Clay pavers are quite common for outdoor use due to their durability, resistance to weather and traffic, their natural hues and ease of installation.

The history of clay pavers as a building material dates back to the Roman Empire, where they were used for paving streets and public squares. Over time, the technology for manufacturing these pavers evolved, allowing the fabrication of more uniform and consistent pieces through mass production techniques, creating more regular and standardized dimensions and shapes. The manufacturing process typically consists of mixing clay with water, extruding, cutting into rectangular or square units, and then firing in a kiln to harden and gain strength.

Even after these advancements, it is still possible to continue improving the manufacturing process and the standards for the installation of the parts. The North American company Endicott Clay Products, based in Nebraska, has been developing clay-based products for more than 100 years. Their latest innovation is the patent-pending Invisi-Lug™ Clay Pavers, minimalist, straight-cornered pieces that feature built-in and hidden spacers. This allows the gaps between pieces to be more consistent and eliminates chipping, provides a crisp square edge aesthetic look, eliminates the need for costly spacers, and improves the speed of installation.

Common clay paving systems use sand, bituminous, or mortar setting beds. For a sand setting bed, the installation of clay pavers is a relatively simple process that involves laying an aggregate, asphalt, cement-treated aggregate, or concrete base, followed by the sand setting bed, where the clay pavers are supported, and interlocked together with jointing sand that is swept and vibrated into the joints between them. Proper spacing between the pavers is something extremely important, as it provides sufficient room for jointing sand to be swept and vibrated between the pavers. The jointing sand provides a cushion between the pieces, helping maintain the same arrangement and interlock between them. As for the interlock, it is important to keep the pavers from twisting and turning over time, allowing for load transfer across joints between pavers.

In the case of Endicott's Invisi-Lug™ pavers, the recessed lugs guarantee the proper joint spacing between the pavers and help eliminate chippage from occurring. This allows a quicker installation process, without worrying about maintaining the proper spacing, and also allows the installer to maintain straight lines and save approximately 25% of the cost versus when a plastic spacer is used.

As it is a natural material, clay pavers can be recycled, containing no harmful chemicals or pollutants. In addition, clay pavers are colorfast and incredibly durable due to the raw materials and the firing process, providing warm, vibrant, and rich shades. Provided in 10 standard Endicott colors that are fired from the same clay and in the same kilns, this provides consistent or complimentary colors between pavers, face brick, and thin brick, important to make the materials match between the building and the walkways.

Endicott's pavers have an average compressive strength of more than 19,000 psi (pounds per square inch), and if installed according to recommended guidelines, can last more than 100 years. In fact, there are many brick streets across the United States with more than 200 years still in use today.

Invisi-Lug™ clay pavers are an excellent choice for paving due to their intrinsic properties, such as malleability and strength, as well as their durability and ease of installation. In addition, because it is a natural material, and with colors impregnated in the piece itself, it becomes a sustainable option that can be easily reused and even recycled after disposal.

Learn more about Endicott's products in our catalog.