Available in many textures, shapes, and colors, these engineered systems, which can be used for walls up to 20 feet high, rely on several techniques including:

• Keyed, battered design (block shapes key into one another and are stacked so they lean into the hillside)
• Backfill trap (block shapes allow backfill to be shoveled into the block webbing, trapping each block individually)
• Geo-grid webs (block maker supplies geo-grid plastic-net tiebacks that attach to the block and are buried 5 feet in the hillside at specific heights).