Randy Clarke has a practiced eye for pavers. He knows how regional differences in aggregate type affect color and texture. He understands how their appearance changes with dry and rainy weather, and he's quick to notice minor variations between individual bricks within a given lot. He's been known to sort through an entire cube of 400 pavers in search of exactly the right shade for the job at hand. He's always on the lookout for remnants of large runs of custom architectural pavers, and he cultivates relationships with suppliers who are willing to turn out limited runs of custom colors for him.

The irregular cutout in this herringbone-pattern layout provides the background for a crossed pair of rose stems, complete with foliage and thorns.
The irregular cutout in this herringbone-pattern layout provides the background for a crossed pair of rose stems, complete with foliage and thorns.
The installer will sweep sand into the joints once the assembly has been installed at the job site.
The installer will sweep sand into the joints once the assembly has been installed at the job site.

But then, that's his job. Clarke's business, RocArt, of Perth, Ont., specializes in detailed mosaics that may contain up to 3,000 full-thickness pieces of interlocking concrete paver. The process starts when Clarke scans a photograph, painting, or other piece of artwork into a computer and uses a graphics program to develop a workable pattern. The individual elements that make up the mosaic — the smallest of which are mere splinters of masonry — are cut to shape with a 14-inch wet saw equipped with a diamond blade.

The precisely cut pieces are then assembled in a wooden frame (or, for a larger mosaic, a series of frames) that has been lined with a tough mat material used in the pulp and paper industry. Once the crated mosaic has been shipped to the job site, the installation crew slides it carefully into position within a previously prepared "background canvas" of pavers, or a blocked-out recess in a concrete slab. While Clarke or a crew member travels from the company's shop to supervise most installations, he has recently trained three installers in Florida and two more in the Chicago area, permitting him to sub out some of the work.

Because individual elements aren't mortared in place, creations are completely portable. If the owners of these mosaics ever move, the pieces can be taken apart and reassembled on a new site.

Most of RocArt's work consists of custom, one-of-a-kind installations on commercial or high-end residential projects. Still, some designs have evolved into standards. The rose pattern pictured here, for example, is a hardy perennial. Harley-Davidson motorcycles are also very popular, and a cache of pavers in just the right shade of blue has landed the company a number of commissions to install oval blue-and-white Ford logos at car and truck dealerships. Prices for RocArt's work range from about $65 per square foot to $300 or more, depending on the level of detail.