Notice in the picture on the right how the grass line increases along the bottom of the building as you move to the right.  The excavation lowered the overall building profile.  The door on the right side of the building is at grade while the entrance on the left is almost three foot above the ground.  The entrance on the left is our main entrance and will require steps, deck and a handicap ramp. 

The length of a handicap ramp is roughly one foot of length for every inch in height.  If our entrance is 36 inches in height from floor to ground, then our ramp would need be approximately 36 feet in length.   Without the excavation, we would have been 60-72 inches above grade which would have required a 60-72 foot handicap ramp.  With the excavation, we reduced the height of the floor level above grade to about three feet reducing the length of our handicap ramp to about 36 feet. 

Excavation is a very useful technique to lower the elevation of a modular building.