How do I stop robins from building a nest by my front door?
Need to stop robins from building.
Hang a small mirror.
Just make it uncomfortable for them. They usually build nests when they feel comfortable. Everytime you see them around you could actually go out there, and they will fly off.
Get a fake owl and put on porch that will stop them.
Stack some boxes up so your cat has access to them.
Shiny objects, moving objects and A predator is all a good idea also the owl. You could also put a cented candle or incense out there, it will only be a few days before the bird gives up on that spot. I like Virginias idea to hang up string.