What Would Cause a Rustling Noise in the Ceiling of a Basement?

Insect Infestation

• Some insects can enter your home and thrive in sufficient numbers to create a rustling sound as they move through the basement ceiling or inside the walls. This especially is common with carpenter ants, which can be found in homes in wooded areas. Carpenter ants can cause structural damage to your home, though they usually enter by eating through rotting wood. This means that if your home already is in need of repair and you hear rustling, it might be too late to prevent significant damage.

Animal Infestation

• Insects aren't the only creatures that can enter your home and nest in the basement ceiling. Mammals -- including squirrels, rats, mice and even bats -- can enter homes in search of food or shelter. Large openings in your basement walls or exterior basement doors may permit larger animals, such as raccoons, to enter. Animals native to your region are the most likely sources of louder sounds that react to noise and vibrations you make by tapping on the ceiling.

Insulation and Isolating Sound

• The presence of insulation in your basement ceiling makes it difficult to diagnose the site and nature of a rustling sound. While larger mammals are likely to make louder noises as they move through a basement ceiling, the sound you hear is affected by not only the size of the animal, but also its distance from you and the amount of insulation between you and the source of the sound.

Following Up

• If the sound you hear in your basement ceiling persists, call an exterminator or animal control service to investigate the issue. If you have a drop ceiling, you might be able to remove a panel at a time when you don't hear any noise to check for additional evidence of infestation, such as chew marks, droppings or nests. However, because some animals can pose significant danger, you should not attempt to confront or trap an invader on your own.