A stacked, mortarless concrete block wall provides the appearance of a solid barrier without using cement. Many interlocking block and brick products on the market allow you to build a wall without cement. For example, you can build a concrete block wall using standard breeze blocks and a few other materials. These walls can be used for borders, non-load-bearing retaining walls and sheds with thin roofs, but mortarless walls should never be used as a structural element.
Lay out a line of concrete blocks along the line of your wall. Place the blocks so that the ends are touching and the sides are flush.
Hold a piece of rebar upright in each hole of the line of blocks. Drive the 6-foot-long rebar 2 feet into the ground with your sledgehammer. Shovel sand into each hole in your blocks.
Place a line of blocks on top of the first. Stagger the seams between blocks by placing a half block in the second row on top of the full block in the first row. Break the block in half by striking the centre gently with your masonry hammer.
Fill the second row of blocks with sand. Check the plumb of the wall with your level. Push or pull the second layer of blocks to keep the wall going straight up.
Add a third row of blocks to the wall. Keep the seams staggered. Drive another piece of rebar into every hole in the blocks leaving 3 feet of rebar above the top of the third row of blocks. Fill the holes with sand. Continue stacking blocks and filling the holes with sand. Be sure to drive a new piece of rebar into every hole in the blocks every three layers.
A bead of caulk can be added to the seams between your blocks to add to the appearance of your wall.
This method of block wall building will not support weight of any kind. This wall is for aesthetic purposes only.