How to Square a Block Wall
- 1). Dig the footing for the wall and pour roughly 6 inches of builder's sand into the footing. Press the sand down with a compressor to create a sturdy foundation for the block wall.
- 2). Lay the first row of blocks end-to-end across the bottom of the footing. Lay a level across the first two blocks to make sure the blocks sit evenly and then across the second and third blocks and so on down the line to make sure all of the blocks sit level.
- 3). Add and remove the sand from beneath blocks as necessary to create a level foundation. Recheck the blocks every time you move the sand until the blocks sit evenly all the way across the foundation.
- 4). Remove the blocks from the footing and spread mortar over the sand. Put the blocks back into place, spreading mortar between the blocks to glue them together.
- 5). Stack the next row of blocks on top of the first row, lining up the edge of the first block with the edge of the block below. Use mortar between the rows of blocks to hold the next row in place. Check the blocks with a level across the row and spread mortar thicker or thinner where necessary to level up the row.
- 6). Place the level against the first blocks in the wall each time you stack a new row to check plumb. Like when checking for levelness, the bubble should appear in the center of the level if the wall is plumb.
- 7). Continue to lay rows of blocks in the same manner. Check for levelness across the row and up the side of the wall as you lay each new row to square the block wall.
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