Determining the Rodent or Pest Scratching in your Wall

I had recently spoken with a customer regarding movement they were hearing in a wall in their house. They were sure it was a squirrel because they had found an entry point in the garage. They consulted with Batzner to discover the next steps. A few days later, I was brushing my teeth in my own bathroom when I heard something in the wall next to me. I turned the toothbrush off and listened again. There it was, a scratching sound directly parallel to my elbow, inside the wall. I pounded on the wall and the noise stopped. A few days later, I heard it again!

I sat down with Paul Matusiak, a 30-year Batzner veteran, and explained the noise in my wall. I also told him about the conversation I had with the customer regarding the squirrel. I wanted to understand how Service Specialists determined what was in a wall, how it got there, and how to get it out.

He asked me the question he always starts with in this scenario. “Was it consistent, or did it stop and start?” Breezes can cause noises that can be heard through the walls, like a loose soffit, for example. Turning a faucet on can test for a loose pipe triggered by running water. If the noise is consistent, it is most likely non-pest related. On the other hand, pest noises are more intermittent as they stop and start whatever they are doing. They may also freeze if they hear noises from you. Matusiak explained that feeling for vibrations can also help determine the cause. Consistent vibrations also indicate a non-pest source. Scratching-type noises can be anything from mice and rats to a large nest of carpenter ants communicating back and forth to wasps, hornets and yes, larger rodents such as squirrels.

Regarding my case, Matusiak explained it would be very rare for a mouse to be inside an interior wall, but as he questioned me further, we hit on a possibility. “It is unlikely a mouse would be in an interior wall on the second floor unless it was near the chimney.” Bingo. I realized the chimney ran right through that area.

For the mouse, baiting in the attic and the basement should do the trick, along with finding and securing the outside opening to ensure more won’t find their way in. Squirrels need to be trapped, so finding their access point is imperative; there are usually two openings far apart. Do NOT block their access before getting them out as they are very destructive and will chew through electrical wires and walls in an attempt to get out. Stinging insects and carpenter ants need to have their nest destroyed, so first identify their access point. Depending on the type of pest, a pest control professional will then treat it by either injecting dust, foam or spray into the wall, and most likely spraying a barrier around the outside of the building.

Regarding the potential damage that can happen if the situation is allowed to progress – carpenter ants, squirrels, and rats can cause expensive damage to a building’s infrastructure. Mice contaminate food and destroy furniture, clothing, and other stored items when they nest in them.

Periodically check the outside of your home, paying close attention to loose or water-damaged soffits. They are often the access point for many pests. Broken sewage pipes, foundation cracks, roof damage, rotted window and door frames, and even the slightest opening is an invitation to unwanted guests.

Hearing something unusual in your wall? Call us at 866-591-3519 or contact us online to determine if further investigation is required to discover the cause.