Northern Ireland recorded its hottest summer since Met Office records began in 1884, with Counties Down, Armagh and Antrim all breaking their own mean temperature records.
Home insurance experts at CompareNI.com said the combination of that heat and the wetter autumn weather now arriving creates ideal conditions for rats to breed over summer and then move indoors in search of food, shelter and warmth as temperatures drop.
Rodent activity has already risen sharply across the UK, with Rentokil Pest Control recording a 10% year-on-year increase in confirmed rat activity and Northern Ireland showing the largest regional rise of any part of the UK, at 26%, ahead of Yorkshire's 20% and north-west England's 19%.
Rentokil has attributed the pattern partly to milder, extended breeding seasons following the UK's run of record-warm years, and separately warned that heavy rainfall can flood burrow systems and drainage networks, forcing rats into buildings in search of higher, drier ground.
Ian Wilson, home insurance expert and managing director at CompareNI.com, said rats are more than a nuisance, capable of causing structural damage by gnawing through electric cables, pipes, insulation and even woodwork. He said most standard home insurance policies do not cover damage caused by vermin, since infestations are typically treated as a preventable maintenance issue rather than an unforeseen risk, meaning homeowners can be left facing a hefty repair bill if a problem isn't tackled early.
That exclusion is consistent with how UK insurers generally treat pest damage more broadly. Standard buildings and contents policies routinely draw a line between sudden, unforeseen events, which are covered, and gradual damage arising from wear, poor maintenance or infestation, which typically isn't, the same underlying logic that has led some insurers to tighten or withdraw cover entirely in other higher-maintenance-risk segments such as thatched roofing.
CompareNI.com noted that buildings cover may still respond to secondary damage caused by an infestation, such as water damage from a pipe a rat has gnawed through, and that home emergency add-on policies can sometimes help cover the cost of pest removal itself, though homeowners need to check their specific policy wording rather than assume either applies.
Wilson recommended homeowners check properties now for gaps or holes rats could use to get in, keep outdoor areas tidy, and fix leaks or drainage issues before colder weather sets in.
CompareNI.com's broader guidance for preventing infestation includes sealing entry points with steel wool, wire mesh or caulk, keeping food storage areas clean and using airtight containers, clearing garden debris and trimming vegetation away from the house, fixing leaking pipes and keeping gutters clear since standing water attracts rats, and using deterrents such as peppermint oil or ultrasonic devices.
It's worth noting that the 26% regional increase figure originates from Rentokil's own reporting of confirmed pest activity between 2024 and 2025, published in March 2026.
That doesn't make the underlying seasonal risk or the insurance guidance any less accurate, however, as rats genuinely do seek shelter indoors as weather cools, and standard policies genuinely do generally exclude vermin damage.
Separately, the claim that failing to declare a rodent infestation during a house sale can constitute mis-selling is consistent with general UK seller disclosure obligations, though the specific conveyancing process and forms involved differ in Northern Ireland from the Property Information Form used in England and Wales, so homeowners should confirm the precise requirement with a solicitor rather than relying on this guidance alone.
A rat infestation sits in the same broad category as many gradual-damage exclusions, where the cost of prevention is trivial compared with the cost of a claim that likely won't be paid.
Given Northern Ireland's confirmed record summer and above-average rat activity increases already recorded before this year's colder months even arrived, the practical advice to seal entry points and address drainage issues now is sound regardless of exactly how fresh the underlying statistics are.
