This is a fourth blog in a series featuring Iowa companies who are making an impact in sustainable construction. The Green Field Products of Dubuque has been making sheets used for counter tops, tabletops, fireplace surrounds or anywhere you would think of using granite. The sheet is made of post consumer waste glass and concrete.
“How the product came into being is a most interesting story.” says owner Tim Greenfield. An architect was visiting another company Tim owns, Dubuque Glass Company, and asked what did they do with the cool glass colored chips in a bin destined for the landfill. Several years later and countless hours of experimentation later, Greenfield Stone was born.
Most of the glass comes from the waste of cutting glass from Dubuque Glass Company. One company’s waste became another company’s supply stream. Mixed in are accent colors like the blue vodka bottle or bottles used at local breweries. However, the biggest seller is one called White Ash which uses different colors of gray glass.
The mix of cement, water, and crushed glass is prepared in a 5 by 10 foot by 1 ¼ inch deep bed and allowed to harden. The sheet is then ground smooth and polished to a gloss finish. The strength of the material is 14,000 pounds per square inch as compared to 4.000psi for typical concrete. Tim says “It is like baking a cake, sometimes the cake is perfect and sometimes it falls in the oven.”
The product is shipped all over the US and costs about $100 per square foot installed. That’s more than granite at $75 per square foot but instead of taking something from the earth you keep bad stuff from going in!!!
If you want to see the product in Des Moines you can find it at Renaissance Marble and Granite in Urbandale.
See the other blogs featuring Iowa companies at IowaBiz sustainable design and construction.
Tags: aia, architects Smith Metzger, ASM, countertop, Green, LEED, recycled glass, recycled products, recycling, residential design, Rob Smith, sustainable design, university renovation
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