Decks, porches and room additions are regulated by the construction codes for each state and/or local housing authority. If the property has an addition attached after the home was sited, the attachment is not regulated by HUD Standards or Regulations. If an addition has been added to a manufactured home, it may take the manufactured home out of conformance with the HUD Standards. The Addition Certification looks to verify if the addition is transferring any load from the addition onto the manufactured home.

There is a simple litmus test to determine if an addition is adding load to the manufactured home. If the home were to magically disappear, what would happen to the addition? Would it continue to stand on its on? Or would it collapse under its own weight?