An infestation of wharf rats, the common brown rat that can take over the tight spaces of a house if left unchecked, can be an annoyance as well as a safety hazard. Many rats can bring with them dangerous communicable diseases, and exterminating the rats yourself as soon as you identify a problem is an important health decision. Proper implementation of traps and repair can end your rat problem.
Search for the location of the rat nest, where the most rats are congregating. If the rats are in your walls or between your floors, you can listen for movement, and track where the most movement occurs.
Locate where the rats have gained access to your house from outdoors. A space as small as a half-inch is enough for a rat to squeeze through and must be sealed off. Caulk any seams along windows that are not properly sealed, and use wood planks for a quick repair to keep rats out of cracks in the exterior of your house if you cannot afford a proper crack sealing.
Bait the snap rat traps with peanut butter. While cheese is often the first image a mouse trap conjures in peoples' minds, peanut butter is the most reliable bait.
Dispose of spent traps, and continue to lay new traps or leave set traps out until you are no longer trapping any rats with them.
Clean the areas that were found to contain rats thoroughly. Remove all droppings, which can spread disease.