PART D - FIRST COURSE OF CONCRETE BLOCKS
Before mixing mortar and laying blocks, you should follow these steps:
Locate the corners of the wall.
Use a chalk line to mark the footing for aligning the first course of blocks.
Check the wall layout by placing the blocks along the wall without mortar. Remember to
leave a 3/8-inch gap between each block for the mortar joint (Figure 2-5). This will tell you
if any cutting is necessary.
Figure 2-5. Laying out block without mortar