Stenciling is generally used in decorative concrete to add patterning effects that are too complex or detailed to be reproduced on concrete through the scoring of lines or through engraving.
Decorative concrete stenciling can be done in a variety of ways. First, a thin cement overlay may be sprayed or troweled over a stencil, and the stencil removed once the overlay has set up and hardened. This is the method used in the photo at right. It is best for repeating, grout-based patterns like brick, cobblestone, flagstone and slate, and it may be used over an entire area or just for a border. The final depth of the grout pattern below the surface of the overlay once the stencil is removed is generally no more than 1/16".
You can see some of the most popular patterns available for stenciled concrete overlays at: Artcrete Concrete Stencils.
Another way stenciling may be done is to etch a pattern into a concrete surface or cement overlay using plain or colored, gelled muriatic acid. This method is best for intricate, curved patterns that require even greater attention to detail than grout-based patterns, like stylish borders and complex custom images, such as family crests or badges. These patterns become a permanent part of the concrete and usually go no deeper than 1/32". You can see samples and read more about this procedure at: Modello Designs and Surface Gel Tek.
Finally, concrete stenciling can be accomplished through the engraving process, as described in our Engraving Services section, or through sandblasting, where a greater physical depth is desired than can be achieved through concrete etching. Below are photos showing an example of a stenciled pattern engraved into concrete.