Like any other wood boring insects, Carpenter bees prefer weathered, rotting and old wood to nest in.
Plugging the holes without removing the infestation can cause these bugs to find alternative paths. Sometimes, they would end up inside your house. So, only plug the entry points after the infestation has been exterminated.
To prevent general wood boring insects (carpenter bees or carpenter ants) from infesting in your house, maintain lower parts of windows and door frames. Usually these frames are made of wood where the paint is peeling off and the caulking is in bad shape. The water would be seeping inside and softening the wood.
The female carpenter bee has a stinger and it is extremely territorial and aggressive.
The nest making damages wood.
The wood shavings as a result of wood boring are an unpleasant sight in the backyards.