Patios stones, walkways and retaining walls. Precision Yardworks has vast experience installing different size and shapes of paving stones and slabs. Starting with a properly sloped compacted base gravel, we then place a layer of weed barrier fabric and final leveling sand before setting the patio stones. This is the basic procedure to ensure a fanastic finished hardscape product. For poured driveways and concrete flatwork we work closely with TR Concrete.