A Simple Exorcism on a home is usually done because the home is being disturbed by something supernatural and it needs immediate attention so that the residents can find some peace.
The Simple Exorcism curbs the power of darkness to help drive away the unwanted paranormal activity. A Prayer to Saint Michael the Archangel is said before it begins. Then the Simple Exorcism Prayer is said in the home along with sprinkling holy water in the rooms.
The Simple Exorcism is an exorcism that can be done on a place and it is not The Rite of Exorcism which is a totally different exorcism that can only be done on a person who is fully possessed and it is intended on casting out the evil spirit that has taken possession of a person. If a person is afflicted by evil spirits and not possessed then Deliverance Prayers are the proper way of getting rid of the evil influence.
In some cases the person themselves are haunted and they will need a Deliverance or Exorcism to get the haunting to go away. In cases for Residual haunts, the haunting activity is just like a recording and happens over and over again and is not harmful.