Step 1: Dig a 7” deep (or more depending on the height of the wall) trench where the retaining wall will be located. Set up a level line using stakes and string along the entire length of the wall, near ground level above the trench. Fill the trench with about 5” compacted gravel. Fill in another 1” with leveling sand. Be sure to follow your level line- this is the most important thing to ensure the retaining wall will look nice and be long lasting.
Step 2: Now that you have a level base to start, place retaining wall blocks in their approximate places. The first row of blocks should be slightly below the ground line. Each individual block will need to be leveled. Use a rubber mallet to pound on the blocks and make adjustments. Check the level left to right and front to back. Once the entire first row of blocks is level, the project is almost finished!
Step 3: Since the first row is already level, simply set the remaining blocks on top of the others, staggering the seams. This will make the wall much stronger. Build one row at a time until the desired height is reached.
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