Rats and Mice: What to Do If You Have a Problem

How to Tell If You Have Rats or Mice

The signs of a rodent infestation are similar for both species, though the scale of the evidence often differs. Mice leave smaller droppings and tend to stay close to walls and skirting boards. Rats leave larger droppings and are more likely to burrow, chew through harder materials, and move through drains and cavities.

Common signs of rats or mice in a property include droppings in cupboards, under sinks, along walls, and in loft spaces. You may notice gnaw marks on food packaging, cables, pipes, or woodwork. Some people hear scratching or movement in walls, ceilings, or under floorboards, particularly at night. There may be a noticeable ammonia-like smell in confined areas where rodents are nesting. In gardens, rat burrows can appear along fence lines, under decking, or beside outbuildings.

If you spot one rat or mouse, there are almost certainly more. Rodents are rarely solitary, and they breed rapidly. A single female mouse can produce over 50 offspring in a year.

Why Rodents Are More Than Just a Nuisance

Rats and mice carry diseases that can be passed to humans through contact with droppings, urine, or contaminated surfaces. Leptospirosis, Salmonella, and Hantavirus are among the conditions associated with rodent infestations. They also carry fleas and ticks into properties.

The structural damage rodents cause is often overlooked until it becomes serious. Rats in particular gnaw through cables, which is a genuine fire risk. They can damage pipework, insulation, and structural timbers. In commercial premises, a rodent infestation can result in enforcement action, failed food hygiene inspections, and significant reputational damage.

Why DIY Treatments Often Fall Short

Shop-bought traps and bait stations can catch individual rodents but rarely resolve an infestation. The underlying access points remain open, food sources go unidentified, and the colony rebuilds quickly.

Rodenticides available to the public are also lower strength than those used by licensed pest controllers. Without a proper survey to establish where rodents are entering, nesting, and feeding, treatment is essentially guesswork.

What a Professional Treatment Involves

A qualified pest controller will begin with a survey of the property to identify entry points, nesting sites, and the extent of the infestation. This shapes the treatment plan rather than applying a one-size-fits-all response.

Treatment typically involves a combination of rodenticide bait stations placed in targeted locations, snap traps where appropriate, and proofing recommendations to prevent re-entry. For rats in particular, drain surveys are sometimes recommended to identify whether the drainage system is providing access.

Follow-up visits allow the pest controller to check bait take, remove dead rodents where accessible, and adjust the programme if needed. Most infestations are resolved within two to three visits, though this depends on the severity and the property type.

Preventing Rodents From Returning

Once a treatment programme is complete, proofing is essential to stop rodents from re-entering. Common entry points include gaps around pipework, damaged air bricks, gaps under doors, and holes in external walls where cables or wires pass through.

Removing food sources also reduces the risk of re-infestation. Secure bin storage, removing bird feeders from gardens, and keeping compost heaps covered all make a property less attractive to rodents.

If you are dealing with rats in a garden or shared outdoor space, it is worth speaking to neighbours. Rodent activity in an area is often shared between multiple properties, and treatment is more effective when it is coordinated.