Compactions, are extremely important in new home, construction,. This is where the foundation will be placed for the new home, to be built on. If the dirt work beneath it is unstable so will the foundation, and your new home, will start to see cracks in places they should not be. Compaction, of a new home pad, may cost more to do but it will cost less than having your house picked up off the foundation to do the work later. I have seen many new homes, that the dirt work was not compacted, and the damage done to it before the home was lifted and after it was lifted and set back in place. The cost is a major cost as well and something that should be avoided if at all possible. Investing the time and money to compact, your new home pad, at the begining is better and far less expensive than doing it after your new home, is resting on the foundation.