Because the eaves of a home make good shelter from the elements, many birds decide on this location to build a nest. Mud and other materials used to build the nest soil your property, as do bird droppings, which if not removed, can become a health hazard. State and federal laws protect most bird species. Destroying their nests or harming the birds, their eggs and their young is illegal. To deter birds from nesting under your roof, make the area uninhabitable and scare away the birds.
Observe the eaves of your home for the beginnings of bird's nests. Use the handle of a broom, or a high-pressure water hose, to knock down or wash away partially completed nests. Remove any nest material from the ground because birds may use it to rebuild. If this happens, destroy the beginning nest again to discourage the birds. If the nest is in its beginning building phase, it's not illegal to destroy it.
Set up metal spikes on the wall under roof eaves to make it impossible for birds to attach a nest to the walls. As an alternative, attach the spikes on ledges that birds may land on while working on building their nests. Metal spikes, also known as porcupine spikes or bird spikes, are needle-like projections that stick out in multiple directions.
Drape bird netting from the outer edge of the roof down to the side foundation of the building. By covering up the roof eaves, birds cannot access the area. As an alternative, use a metal or fiberglass panel in a similar fashion.
Use a combination of visual scare tactics to keep birds away. Hang strips of foil down from the roof; set up a fake predator animal, such as an owl or hawk. Draw scary eyes on bright balloons and hang them in front of the roof eaves.
Purchase a cassette tape with sounds made by bird predators, or a tape with distress calls from birds being attacked. Play the tape in a portable stereo system before nighttime and early in the morning. Move the stereo around daily, so the sound comes from different directions and birds don't get used to them. Avoid playing the sounds at nighttime, because once birds settle for the night, they are hard to deter.