1. Don't clean up the debris and rubbish in the bird's nest immediately, because swallows may still be watching the bird's nest nearby. If swallows are not disturbed, they will repair their nests as soon as possible and continue to hatch or raise young birds.
2. If the swallows have left, you can clean up the garbage and debris around the bird's nest so as to provide a clean environment for them to rebuild their homes.
If swallows are still nearby, they may panic and try to recycle the available materials in the old nest to build the nest. This may prevent them from starting again in the new position, so they should clean up the wreckage and garbage as soon as possible.
4. If the nest is completely destroyed, other site selection can be provided for swallows. You can install a bird's nest box on a nearby tree or hang a suitable bird's nest box on the balcony to provide a new home for swallows.
In a word, when dealing with the nest in front of the house, the safety and interests of swallows should be given priority, and appropriate environment should be provided as much as possible to help them build or move their nests.