Millions of rats are expected to infest UK homes in the near future, looking for a warm space to nest as the weather gets colder, experts have warned. More than 120 million brown rats are likely to enter homes nationwide, and could leave destruction in their wake as they gnaw through cables and wooden beams. The animals, which can have up to six litters a year, typically nest under stairs, in cupboards and in lofts. Paul Bates, of Cleankill Pest Control, told The Sun, "Recent heavy rain has forced many rats above ground. "There is lots of food around for rats at the moment, with ripe fruit and crops from harvesting, so the rat population is peaking at the moment. "As it gets colder, however, as it is now, rats will move closer to food supplies indoors and for somewhere warm to nest - that means people's homes." The best way to protect your house is to clean up food debris and plug any holes in walls, he added. The increased number of rats comes as no surprise to many in the know. Pest control firms report that they typically experience a 30 to 40 per cent rise in infestation call-outs at this time of the year. How to keep rats away Other advice for keeping rats away from your house includes trimming tree branches near the house to eliminate ways that they can climb in and removing ivy or vines on walls. Tree guards around the base of trees can also help to stop rats from climbing. Limiting outdoor water sources and also keeping lids on your bins can help to deter rats as they don’t see your home as an easy source of food and drink. You can also buy various rat repellants, however the success of these is doubtful. If you are going to use traps, but rat-specific ones as normal mouse traps will not work. How to spot a rat infestation Rat droppings around food packages, in drawers and cupboards and under the sinkEvidence of gnawing on food packaging or other materialsRat tracks (footprints or tail marks)Nest materials such as shredded paper, furniture stuffing or other soft materialScurrying sounds or squeaking in wallsBurrowsDead rats