Page 28 - April 2022 Slippery Rock Gazette

28|April 2022
Slippery rock GAzette
Manufacturing Impacts: Natural Stone vs. Sintered
Sintered surface, also known as ultra-compact surface, is an engineered product that
is dense, durable, and resistant to stains, heat, and scratches. The material can be used in many dif- ferent applications including inte- rior kitchens and bathrooms, and exterior applications such as wall cladding and countertops. This is due to the material’s various thicknesses and durability, and because it has a low porosity and does not fade from UV exposure.
With Sintered material, the intended pattern or design gets printed on the surface but typ- ically does not go all the way through the material. This means that the ends and edges may not have the same color or pattern as the rest of the surface. Sintered surface has an increased risk of chipping due to its denseness and hardness. The edges are especially prone to damage if impacted and can be difficult to repair.
Sintered surface is sometimes marketed as sustainable because it contains natural materials. But as you will see from the manufac- turing process described below, the use of an energy intensive manufacturingprocessgivessin- tered surface a much larger envi- ronmental footprint than natural stone.
Manufacturing Sintered Surface vs. Natural Stone
Sintered surfaces are created with several natural materials including kaolin, feldspars, sili- co-aluminates, and clays, which are first mined out of the ground. The raw materials are then trans- ported to a manufacturing plant, where they must then undergo a complex, energy intensive pro- cess that simulates, or mimics, hundreds of years of metamorphic
Stephanie Vierra, Assoc. AIA, LEED AP BD+C Vierra Design & Education Services, LLC Reprinted by Permission usenaturalstone.org
Manufacturing Impacts of Sintered Surface
Manufacturing Impacts of Natural Stone
A sintered stone slab with an interesting texture ready for use as a countertop. Photo Credit: Wikimedia Commons/JonSmith37341.
Global Warming Potential by Material
This chart compares the Global Warming Potential (expressed as kg CO2 eq) of the product manufacturing phase (A1-A3) documented in the LCA results published within EPDs, for a variety of products. Data averaged when multiple EPDs were used. All functional units converted to 1 ton.
This stone fabrication plant recycles and reuses water in the polish- ing stage, saving thousands of gallons of water annually.
Photo Credit: Dennett Tile & Stone
change. To manufacture a sintered surface requires several differ- ent stages of processing includ- ing grinding, mixing, reacting, stabilizing, separating, and dry- ing. This resulting mixture is then subjected to immense pressure and extreme heat—more than 2,000° F—to fuse the materials together, all of which requires a lot of energy.
In contrast, natural stone requires only quarrying, fabricat- ing, finishing, and transporting. No additive materials or chemi- cals are required to create natural stone. Stone is formed naturally by the Earth over time. Several types of natural stone, including marble and gneiss, undergo meta- morphoses within the Earth’s crust where extreme pressure and heat transform the deposit from a more porous material to a harder and denser material. This pro- cess happens over millions of years in the ground. This means natural stone really is a natu- ral material and has many other
attributes, including its durabil- ity, recyclability, and wide range of aesthetics. Natural stone can be used in many different indoor and outdoor applications as well and contains no Volatile Organic Compounds (VOCs), meaning it does not emit any harmful gases, making it a healthy material.
Sustainability Concerns
From an overall sustainability perspective,naturalstonehasa much lower environmental foot- print than a sintered surface. This is due to the minimal resources used to quarry, fabricate, finish, and transport natural stone. As the graph below demonstrates, a sin- tered surface has a much higher global warming potential (GWP) than natural stone and a few other building materials. Each step in the sintered surface manufactur- ing process requires the use of a lot of energy, which contributes to a large GWP. The larger the GWP, the more that a given gas warms the Earth compared to car- bon dioxide (CO2) over the same time frame.
The impacts of these processes have been documented and sys- tematically compared against other materials using the same environmental criteria. This infor- mation is a valuable resource when selecting a sustainable material for a project.
These characteristics and attri- butes also make natural stone
a great choice when seeking a green building rating certification within the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) or the International Living Future Institute’s Living Building Challenge (LBC).
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Kaolin, Feldspars, Silico Aluminates and Clays are Mined
Raw Materials Transported to Manufacturing Plant
Ingredients Go Through Several Stages of Processing, Including: Grinding, Mixing, Reacting, Stabilizing, Separating, and Drying. The Resulting Mixture is Subjected to Immense Pressure then Extreme Heat, and Pressed.