How to Build a Short Round Cinder Block Wall

Use a garden hose to define the outline of the entire wall. Measure out an area twice as wide as the thickness of the wall. For example, measure a border 16-inches wide for an 8-inch wide wall. Dig least 8 inches deep with a shovel to reach below the frost line.

Mix concrete mixture in a wheelbarrow with a shovel to fill the trench. This is known as the footer, and all block walls need one to provide adequate support so the wall doesn’t sink into the ground over time. Let the footer dry for at least 24 hours before setting the block on top of it, although 72 hours is advised.

Prepare another batch of concrete mix in your wheelbarrow to use as the mortar for the actual blocks. Spread an inch of the mixture over the footer for your base layer of blocks. Set your base layer across the top of the footer along the radius, keeping the blocks approximately a half inch from each other. Put mortar down between blocks with the mason trowel and tap them together gently with the rubber mallet.

Level the first layer after all of the blocks are in place. Place the level on top of the wall across the blocks and tap them gently into place if they are uneven.

Spread three-quarters to a full inch of mortar on top of the first row of radius blocks for the second row. Set your second layer of radius blocks on top of the first layer, alternating pieces, so the vertical joints from the first row line up with the middle of the blocks on the second row. Repeat the leveling process for each block.

Use a level to check for plumb after completing two or three more rows. Use the rubber mallet to help level the wall needed, so that you can keep the wall plumb both horizontally and vertically. Finish the wall and scrape the excess mortar away from the wall's face with the mason trowel.