Mice in the House

mice in the house

Mice are one of the most common pests worldwide. These small rodents are constantly invading our homes and businesses. Urbanisation and global trade have only increased their presence in urban, and rural, environments. One place which mice are constantly inhabiting are residential areas, but what makes your home so attractive to mice?

Why my home?

You’ve probably encountered, or know someone who has, a mouse infestation in your home. Finding mice in the house is a big problem for many people around the world.

Your home is a great place for mice to inhabit due to two key factors:

  • Food
  • Shelter


A constant supply of food is what makes your home so attractive to mice. Mice are excellent scavengers with a pretty huge diet range. They will eat almost anything, but they do have a preference for grains.

Your home is full of a wide variety of different food for mice to get their teeth stuck into. The constant supply means they never have to travel far for a midnight snack, and as they are creatures of habit this works out perfectly for them.


Another reason for a mice infestation in a house is shelter. Mice are quite adaptable to any environment, but when the nights get longer and colder, they like to migrate to our homes to escape the elements.

A residential property provides numerous areas for a house to live, this could be high up in the beams of your attic, or underneath the floorboards of your kitchen.

Types of Mice

Depending on where you live, there are a range of different mice that can invade your home. Although they more or less behave in the same way, each species of mice utilize and invade your home in slightly different ways to one another.

House Mouse

House mouse - mice in home

The most common species worldwide is the house mouse (Mus musculus), which invade buildings all year round and survive on a wide variety of foods.

House mice are usually ground living and tend to burrow their nests into the ground. However, they are still really good climbers. If you are unlucky enough to have this mouse in your home then your breakfast cereals might start to disappear.

What do house mice look like?

  • 70-95mm in length
  • Tail the same size as body
  • Small feet and head
  • Large ears and eyes
  • Light brown or gray to black in colour

Field mouse

Field Mouse - mice in home

The European wood mouse/ field mouse (eg Apodemus sylvaticus) is common throughout Europe. Compared to house mice, field mice tend to be a pest particularly in the winter months when they seek shelter in buildings during the harsh season.  Seeds make up a large part of their diet.

However, a field mouse infestation in your house could result in nibbles to your fresh fruit.

What do field mice look like?

  • Head and body around 80-100mm in length, Tail 70-90mm
  • They can weigh between 20g and 25g depending on gender
  • Sandy/orange brown in colour with a small yellow streak on their chest.

Deer Mice

Deer Mouse - mice in home

The deer mouse (Peromyscus maniculatus) is the main indigenous pest in North America. Deer mice are nocturnal, and come out at night time to feed. Deer mice are excellent climbers.

If you have deer mice in your house you can usually find them in the attic and upper floors. Deer mice are also one of the leading carriers of Hantavirus.

What do deer mice look like?

  • Head and body 2.75”-4” with the tail 2-5”
  • They can weigh between 0.38 and 1.25oz
  • Reddish brown colour on top with white fur on the belly
  • Tale is usually bi-coloured and longer than half the length of their body

How do mice get into your home?

Mice in homeMice can get into your home through poor design and build quality. As time, progresses houses start to deteriorate. This can be due to normal wear and tear, and as a result, mice gain an opportunity to invade your home.

Common entry points for mice

There are a handful of entry points mice can use to get into houses, flats and apartment buildings. Once a mouse has navigated its way into a home, it can quickly become a large problem due to their high breeding rate.


Mice in the attic can be a big problem for some people. Mice can access attics via:

  • vents,
  • cables,
  • pipework
  • walls

Attics provide mice with a key point to gain entry to your home. It allows them to easily travel from room to room through gaps under the roof, along pipes, ducts, and wiring – this is often referred to as mice motorways.

Attics also provide a good living space for mice.  Stored items in cardboard boxes and insulation supply them with a great source of nesting material.


Basements and cellars can have multiple entry points for mice such as air vents, piping and small cracks and holes. Basements provide mice with a great place to live during the colder months.

These areas also provide mice with further access to a home via pipework, cable ducting, shafts. This allows them to quickly, and safely, navigate a property, allowing them to fully inhabit a home.


As excellent climbers, mice can navigate to the roof of your home quickly and easily. Mice can use chimneys to enter your home through the gaps and cracks in the cement, brickwork, and roof tiles.


Badly fitted and damaged doors and frames can also be used by mice to gain access to your property. The gaps underneath the doors, plus any damages, provide mice with an easy passageway into your home.


Windows can also provide mice with easy access to your home. Badly fitting and damaged or decayed window frames could provide an opportunity for mice to get into your home.

Lift shaft

Lift shafts in apartment buildings also provide an easy access point. Mice can use the cables, pipes and rails to climb and navigate a building. Essentially what lift shafts do is provide mice with a giant climbing frame which allows them to gain access to multiple properties.


Mice often use roofs to gain access to a home. Roofs provide mice with a range of entry points such as roof tiles and chimneys. If damaged, these features can help mice gain access to your home.

Roofs also provide mice with a range of different climbing apparatus such as cables, overhanging branches, and hanging plants such as ivy, allowing them to quickly navigate the outside of your home.


Mice in your garage can be a big problem. Mice can often find their way into garages through ill-fitted doors and damages to the brickwork. Garages are often filled with food and other items such as cardboard and paper – something mice love to build their nests with.

In cases where garages are attached to a home, mice in a garage can often lead to a full infestation of a property.

Keeping mice out of the house

The best way to get rid of mice in the house is to prevent mice from entering in the first place. Mouse proofing your home can be done by yourself at little to no cost.

Remove food

Mouse eating - mice in homeAlthough they don’t need much water to survive, they do need a constant supply of food which is easily accessible. Removing potential food sources from your home will make it far less attractive for mice.

Mice only need small quantities of food to survive. Even something simple as clearing away crumbs can go a long way when preventing mice.

You can prevent mice by:

  • Store foods such as cereal, seeds, and pet food in airtight containers made of metal or plastic.
  • Keep food off the floor and regularly clean surfaces and floors from any food debris.
  • Empty bins daily and ensure lids are always kept on. Although the food we discard might seem unpalatable to us, it’s a different story for mice.

Block entry and access routes

As you probably already know from reading this blog, damages to your home’s exterior provide a gateway for mice into your home. You can mouse-proof your home by regularly checking the access points listed above for any damages and repair if necessary.

Remember mice only need a hole the size of a pencil to get into your home, what might seem too small to you, is no issue for a mouse.

You can prevent mice by:

  • Use fillers such as expanding foam to fill in any gaps and cracks in and around your home, playing close attention to areas such as around pipes and floorboards.
  • Install bristle strips underneath doors to stop mice from squeezing underneath.
  • Cover air vents with wire mesh – this not only helps keep mice out but doesn’t restrict the airflow of your property.

If you do have a mouse infestation, make sure you get rid of them first before eliminating the entry points – you might find yourself with a litter of dead rodents trapped in your walls. This can not only create a bad smell but it can attract other pests such as flies, but also lead to a handful of rodent-borne diseases being spread. In cases such as this, your best option is to contact a professional pest controller to help assist you in managing your rodent problem.