house-warming 
noun [usually as modifier]
A party celebrating a move to a new home: a house-warming party...
- Well, hey, once you're done moving everything in maybe we should have a house-warming party for you or something.
- One neighbour, who did not want to be named, said: ‘We had a house-warming party and he came along, we always got a Christmas card from him.’
- But should they get the house, they will be faced with one enormous problem - they have promised every one who votes for them that they will be having a house-warming party.