Dig out your area by hand or by machine to allow for 50-100mm of cracker dust substrate, as well as the height of your artificial grass.
Tip: Where the artificial grass will meet you outdoor finished floor level (FFL) such as a driveway or paved area, you may choose to install the artificial grass with the blades protruding approximately 5-10mm above the FFL for a more natural look. Based on a reasonably flat area, you can use your square meterage to determine how many cubic metres of sand will need to be removed, and therefore what skip bin size you may need (if using one). However, often landscape levels are undulating, and it can be difficult to calculate the quantity of sand that will come out. Even a small variation in levels can equate to a sizeable difference in sand quantities.
Around the perimeter, aim to excavate to the depth of the cracker dust you will place plus the height of your artificial grass, subtracting how far the artificial grass will protrude above your FFL.
For example, if installing 70mm of cracker dust and installing artificial grass with a 35mm pile height that will protrude 10mm above FFL, excavate 70mm + 35mm – 10mm, approximately 95mm below FFL around the perimeter.