A stackable retaining wall is a landscaping element made from stackable objects, such as bricks, concrete blocks or stones. Stackable retaining walls reduce soil erosion and add visual interest to the landscape.
Interlocking concrete blocks are a popular choice for stackable retaining walls. They come in a variety of sizes, shapes and colors and have decorative front faces. The blocks don't require bonding with mortar, cement or adhesive.
Stackable retaining walls under 4 feet in height typically don't require building permits, according to Today's Homeowner. In addition to a permit, higher walls often require extra structural support and benefit from professional installation.