Rats and mice are common pests in North America. The rodents may move into your home to escape the cold or to find food. They may set up residence within your house's walls, as the dark and insulated spaces between the walls create a prime habitat for breeding. You may hear the rodents chewing your walls or running along the baseboards. Take steps to poison and trap the rats and mice before they cause extensive damage to your walls or household wiring.
Remove the plastic faceplates from an electrical socket or light switch on the wall in which you hear mice or rats gnawing. Depending on the outlet or switch's construction, you may need a screwdriver.
Insert a plastic funnel into the exposed outlet or switch hole. Pour a dosage of granulated rodent poison through the funnel. Different types of rodenticides are available commercially, including anticoagulants and baits formulated with metal phosphides or calciferols. This is the best way to get poison between your home's walls. Follow the guidelines on the poison's package for dosage amount, as potency and toxicity vary by product.
Replace the plastic cover on the switch or outlet. The rats or mice will discover the poison within the walls and consume it, effectively killing them.
Set up lethal or non-lethal rodent traps near water sources in your home, such as under your kitchen sink. The rats and mice will be forced to exit your walls in search of moisture. Mouse and rat traps can be obtained from most general retailers. Exercise caution in using traps if you have small children or household pets.
Turn on an ultrasonic pest repellent device near problem areas where mice and rats are chewing on your walls. These devices may run on batteries or need to be plugged into an outlet. They emit a high-pitched noise that is imperceptible to humans but irritates and drives rodents away. Run the device whenever you notice a rodent problem.
Inspect your home for common entrance areas for rats and mice. These include doors that don't close fully, tears in your window's screens, and gaps in the wall where exterior pipes enter the house. Seal these areas with caulk.