By tilling dry Portland into the ground 4 to 5 inches, compacting and
moistening it, you are creating a strong sub-base that will resist ground movement and keep your project looking great for years to come. This process is only recommended if you have sandy type soils. If you have the clay type of soils it is recommended that you excavate enough material out to put down 4 to 6 inches of crushed limestone or road base material and compact it before you screed your 1 inch of bedding sand. On paver projects, the base preparation is the most important part, so take a little extra time and effort on your base to make your project look great.