StoneCoat Hydraulic Limestone Veneer

Words: Hector KarrmasonryStoneCoat, a new hydraulic limestone application system, is a mixture of limestone and other natural materials. It is an architecturally certified product that can be blown onto almost any surface, where it then can be handcrafted, shaped and colored in a variety of ways. This recreates the look of flagstone, cut or quarried stone, river rock, brick or slate.

StoneCoat is a material that has been used in Europe for decades. The base materials come from just two quarries in Europe and cannot be duplicated in the United States. The materials have been available in the U.S. for only eight years. During this time, the technology has been most prevalent in the South and is now being marketed in the northern states, but not extensively.

The process

StoneCoat is a natural, hydraulic limestone that is crushed, mixed with a proprietary binder and spray applied to any surface (other than vinyl, aluminum or steel siding) and hand carved to match any stone, brick, block or river rock design you can imagine.

This quarried stone is crushed to a powder, and then re-bonded with water. The mixture is next applied to a surface where the water evaporates and the mix absorbs carbon dioxide. The results create a solid and strong limestone masonry veneer that is vapor permeable, breathable, and resistant to bacteria, salts and chlorine.

The mixture can be applied to dry wall, rough coat, wood over lath, ICF, brick, cinder block, plywood (OSB) and even ceilings. Carving designs into the mixture takes place during the drying period, which is between six and nine hours. You can enhance the look by adding color: olive, natural, black, gold, red, and a variety of browns — light, medium, chocolate and dark.

The temperature for installing StoneCoat must be 40 degrees or higher, and the final hardening and curing process takes 28 days.

The benefits

StoneCoat takes less time to install than cut or quarried stone and brick, at a rate of 600 to 800 square feet per day. It is lightweight at 6 pounds per square foot, making it less restrictive and less labor intensive than traditional brick and stone. It is self-supporting and does not require a brick ledge or a footing.

StoneCoat is environmentally friendly; it breathes, is mold resistant, and absorbs carbon dioxide. The product is real stone, not manufactured, faux or cement based. It is 95 percent limestone (CaCO3) with a 5 percent additive that allows the product to retain the correct moisture, adhere to surfaces, and cure quickly.

It is not designed to support structures or recommended for floorings with heavy foot traffic, and it is warrantied for the life of the structure to which it is applied.
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