You should make it a rule to clean Domik Ptashki every year. After the birds left their house, it must be removed, opened, cleaned of contents, scald the inside with boiling water or treated with a solution of potassium permanganate to remove parasites.
If a crack appears on the birdhouse, do not rush to close it yourself, the birds will repair small cracks themselves. If you decide to restore the house, use only natural materials: tow, wood, clay or natural wax. The house should be repaired only outside. Do not use glue, paint and other chemicals to repair, this can scare away birds.