If you see one rat on your property, there are more nearby. Because rats live in colonies, you may have an infestation. Groups of rats can cause a lot of damage to your home. You must deal with them immediately because the damage they create can become extensive quickly.

One of their most valuable tools of destruction is their teeth. Rats can chew through most materials found in and around homes, making your home vulnerable to entry. A rat only needs a hole the size of a quarter to access a structure. With smaller holes or cracks, they will gnaw it until it becomes the size of a quarter or larger, then enter.

Homeowners must act if they see chew marks anywhere on the interior or exterior of their home or other structures on the property. These could be sure signs of a rat problem or activity of other nuisance wildlife.

Why Do Rats Gnaw?

Rats have 16 teeth, including four incisors and 12 molars. The incisors are the number one reason rats gnaw and chew on whatever they can find. Rats have incisors that continually grow throughout their lifetime. Incisors are the front teeth, two at the top and two at the bottom of the mouth. They are typically long and extend further under the gums.

Rats’ incisors can grow several inches in a year, which would cause severe pain for the animal. Therefore, they chew on materials in their environment to grind the incisors to keep them filed and pain-free. If living on your property, the materials they find may be in your home. Amazingly, rats can bite six times per second and, with each bite, can exert 7,000 pounds of force for one square inch.

Their jaw strength is comparable to much larger animals. It is understandable why it can chew through most home-building materials. If the material is not stronger than the incisors, rats can gnaw and chew without problems.

Six Materials Rats Gnaw Through

If you suspect rat activity inside or outside your home, you may be surprised where you can find gnaw marks. The most common materials include the following:

  1. Wood, like pantry cabinets, as they raid groceries, baseboards as they travel back and forth from a nest, furniture, wood beams in an attic, or the wood behind walls.
  2. Cardboard, including any boxes used for storage, like cereals, pasta, pet feed, paper goods, or sentimental items.
  3. Drywall inside and outside walls, attics, and ceilings.
  4. Plastics, including food storage containers in a pantry, water bottles, and liters of soda. Pet food stored in plastic tubs in a garage is also vulnerable.
  5. Aluminum, like in flashing, caps, under metal roofing, or aluminum siding. They may gnaw on soda cans, shopping bags, toothpaste containers, and many other daily products.
  6. Electrical wiring, such as the cords powering television, internet, lamps, and appliances. Older electrical wires may have aluminum.

Rats can cost you a lot of money in repairs by gnawing on materials in less common areas, like the following:

  1. Soft concrete may include concrete walls, pavers, patio, or porch slabs. Posts around fences and gardens are usually set with smooth concrete.
  2. PVC piping, including the materials for HVAC ducts, plumbing, washing machines, dishwashers, and drainage systems.
  3. Brick for covering the outside of a home, driveway, or patio.
  4. Lead is found in the paint, toys, stained glass, dishware, and some jewelry in older homes.

The hardest materials a rat can chew through are wood, thick beams, and boards that provide structural support. They can also chew through soft brick and concrete that is not cured correctly. Rats may make a small crack in the brick-and-mortar surrounding your chimney into a big hole that causes bricks to fall apart, exposing your home’s interior. Cracks in concrete surfaces also make it easier for rats to chew larger openings.

Four Things Rats Cannot Chew Through

Any materials with greater strength than their incisors are too difficult for them to chew on or through. Examples of hard materials include:

  1. Steel, like sinks, ovens, refrigerators, steel beams, steel wiring in ductwork, and fencing.
  2. Iron to reinforce concrete and other structures. Some homes have iron sewer pipes, cisterns, or water piping. Some use it as a decorative material.
  3. Solid concrete, like many home foundations.
  4. Stones for building barriers around the foundation of a home or as exterior siding, veneered interior walls, and flooring.

Why Do Rats Chew Electrical Wires?

Electrical wiring contains various materials, from thin metals and rubber to plastics. Rats chew on electrical wires for several reasons, including keeping their teeth filed down. They typically pick items that are in their way during daily travels. Sometimes, they choose to gnaw on wires simply because they are in the way.

Wires are easy to hold, allowing rats to get a good grip while gnawing. They can better control the process. If you notice bite marks on wires, contact a professional wildlife expert for help. Gnawed electrical cables can cause a house fire, shut down security systems, break appliances, and even cause your car to malfunction if rats chew on mechanical wires in your vehicle.

Another reason rats chew on electrical wires is that they are attracted to the ingredients within the wires. For example, some wire insulation is soy-based. Other wires, especially car wires, may be made using peanut oil, rice husks, and other plant-based materials. When some wires are warm, they can produce an aroma, like vanilla, which will attract rats.

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