It is best to eradicate rats and mice quickly, even if it appears to be just one running around in the dead of night. The mess they leave and the damage they will do to your home can be costly and timely to fix. Often the damage is outright dangerous, or their hygiene habits leave you, your family, or beloved pets feeling ill.
Rats and mice both need to gnaw on things. Their teeth continue to grow throughout their life. Their incisors curve as they grow and gnawing on things like timber and pipes helps control this growth. If a rodent’s incisors get too long it won’t be able to eat, chewing through that water pipe is like a trip to the dentist. This means they will chew on house timber and plastic waterpipes, not just for fun but because they need to!
I’ve been to many jobs in response to rodents chewing pipes long before they have eaten any poison. The worst case being a home vacant for 2 years where the rats had chewed water pipes in more than a dozen places. The homeowner returned from overseas to almost every room in the house flooded.
Power cables, network cables, and phone cables are all critical services rodents love to chew on. This behaviour often causes faults to alarm systems, internet connections, central heating units, and can create a fire risk when damaging mains supply wiring.
When a hole is too small for rats and mice to fit through they will make short work of increasing its size eating their way through walls, floors, and sometimes doors. Rat teeth rank about 5.5 on the Mohs Scale, this means their teeth are harder than iron and copper so a lot of materials in our homes are no match for their chewing behaviours. Rodents will often chew holes through the rubber seal on the bottom of garage doors to gain access.
Mice commonly eat away at carpet under interior doors for the same reason. An adult mouse can squeeze through a hole 10mm round but they like to go places fast, rats will go through a hole 25mm round but just like mice they don’t like to mess around, quick access to get in and get out is what they are after. Rats and mice will chew through walls if there is any gap letting light through. Inside walls they even chew around the base of the vertical studs to make their passage easier to travel along. Rats and mice chewing through ceilings is not unheard of either.
Both rats and mice build nests, sometimes bringing in materials from outside, both love insulation. They burrow into any insulation that is made of fibre, like pink batts. They will make a hell of a mess and destroy the insulation. Mice also love to build nests in the motor compartment of fridges. Often this means they stay warm because of the motor and they are nice and close to a food source in the kitchen. Mice will quite happily live very close to people even nesting inside lounge suites, bottom drawers, wardrobes, in a suitcase under your bed, and many other places.
Rats however are not so comfortable usually sticking to places a little further way, both will nest happily in a hot water cupboard for the warmth often staining and ruining any linen or clothes kept there. Rodents have been known to crawl up through the floor and build a nest under baths and shower bases. Even when well-sealed the smell of rodent urine can still get through and often the only fix is to remove the bath or shower base to clean up the nest site.
Rodent urine will stain surfaces and leave a horrid smell that can take months to fade away. Rats in a roof space will have a latrine site where they leave waste food and do their business. Their urine can soak through Gib ceilings and the only fix is to replace the ceiling. The smell can be so strong you can tell a place has rats as soon as you walk in the front door. Not only does it smell but their toilet habits can spread disease like leptospirosis (A bacterial disease spread through the urine of infected animals.
When rodents get into your pantry it can be costly. Rats and mice have similar and extremely diverse diets. There is not a lot they can’t or won’t eat, they will try a bite of anything if they have easy access. Bread and flour are always high on the menu for rodents, mice will even tunnel through the back of a bag of flour carving it out from the inside. Mice being smaller can often be a bit more discreet when eating through your food stores and evidence may not be as easily spotted at first glance. Rats being much larger tend to move stuff around and make a bigger mess of what they are eating.
Both can be hoarders and will make several trips to collect food from your pantry. Human food is not the only target, pet food is also well liked by rats and mice. In some cases, rats will pile dog and cat biscuits up under ovens, behind fridges, behind couches and other furniture on the way back to their nests. This will contaminate your pet’s food spreading disease to your pets. Therefore it’s important to throw away your pets’ food too.