There are many different things that people put on cakes for a new house. The most common thing that people put on cakes for a new house is a housewarming message. Other common things that people put on cakes for a new house include:
-The address of the new house
-The date that the family moved in
-The family's new last name (if they've changed it)
-A message of congratulations
There are many different ways that you can decorate a cake for a new house. You can use fondant to create a realistic looking house, or you can use icing to create a more abstract design. You can also use edible markers to write a message on the cake. Whatever you decide to do, make sure that the cake is big enough to feed all of the guests at the housewarming party.