I understand that there are also good days and auspicious time during qing ming and even during the lunar ghost month. You can check a reliable tong shu or chinese almanac. If you are following that, you will need to check that it does not conflict with the chinese horoscope of those people who are going to stay in the new house.
But if opening the door during qing ming bothers you or your parents, you may want to do it on another date. It's always good to do things harmoniously in the family.