They can, so the real protection is giving them nothing to come for. A mouse can squeeze through a gap as small as 5mm, and plastic is something mice can gnaw: university pest guidance notes that they chew on the very storage containers meant to keep food safe from them. So a plastic box helps, but it isn't a guarantee. What draws mice and insects is food, and soft material to nest in or feed on. Our terms don't allow food or perishables in a unit unless they're securely packed so they're protected from, and don't attract, vermin. On our side, our guide to how safe self storage is describes how we seal off entry points, keep sites clean and carry out inspections and preventative pest control. On your side, packing clean, dry and food-free takes away the food. Cloth, wool and paper still attract mice looking for nesting material, so keep those in closed containers off the floor.
What we do on our sites
Our guide to how safe self storage is sets out how we keep pests out: "we seal off potential entry points, maintain a high level of cleanliness, and carry out regular inspections and preventative pest control measures." That's a guide rather than a clause in your agreement, and it doesn't give a schedule, so if how often a site is checked matters to you, ask us when you book. That work covers the building and the corridors. It can't control what goes into each unit, and food in one unit can draw mice into a building shared with everyone else's belongings. That's why the food rule below exists, and why it applies to everyone.
What brings pests in
Food. Mice will eat almost anything, and cereal products are a favourite, according to the British Pest Control Association. Clause 18(a) of our terms says you must not store "food or perishable goods unless securely packed so they are protected from and do not attract vermin". Under the agreement, unopened tins and sealed jars packed so they can't attract vermin can go in; tell us when you book. Fresh, chilled, frozen or opened food can't, and that includes the forgotten biscuits in a drawer. Ask us before you store anything else, such as repacked dry goods, pet food or bird seed. Our short list of prohibited goods is stricter and simply names food or perishables, so the fewer food smells in your unit, the less there is to draw mice. Our guide to storing food in a storage unit goes through what "securely packed" means in practice. Our terms also rule out anything that gives off odours (clause 18(f)).
Nesting material. Mice build nests from cloth, wool and paper, and they gnaw continually on wood, carpets, paper, cables and furniture. Rats and mice have to gnaw to keep their teeth worn down, so they chew things they can't eat.
Natural-fibre fabric. Clothes moths and carpet beetle larvae feed on animal fibres: wool, fur, silk, cashmere, feathers and hair. The Museums Association's pest guide calls the carpet beetle larva Britain's major textile pest.
Plastic boxes, cardboard and what actually holds
| Container | Against mice | Against insects | Best for |
|---|---|---|---|
| Cardboard box | Little: paper and card are nesting material. Paper packaging inside a cardboard outer is the weakest combination | Some, while taped shut, but card isn't a sealed barrier | Clean, dry, non-food household items, taped shut |
| Plastic tub with a tight lid | Better, but mice can chew plastic | Good, if the lid fits | Clean, bone-dry textiles and paperwork |
| Glass jar or metal tin | Good: pest guidance recommends these for food | Good | Food, where it can go in at all (sealed tins and jars; ask us about anything else) |
Plastic helps mostly because it closes: an insect can't wander in, and nothing inside smells of food. Pest-control guidance lists plastic among the materials mice can gnaw, which is why it recommends metal or concrete for sealing holes, and glass jars or metal tins for dried food. So a tub of clean jumpers is well protected; a tub with a packet of crisps in it isn't.
A closed box has one catch. Anything that goes in damp stays damp, and fabric shut in with moisture can go musty or mouldy. The Museums Association's guide suggests airtight containers or plastic garment bags for fabric going into long-term storage; our guide to stopping clothes going musty in storage prefers packing that lets air through. Both depend on the same condition: the fabric is clean and completely dry. For quilts, a wool rug or bedding kept for a year or more, wash or clean it, dry it right through, wrap it in cotton, and put it in a lidded tub off the floor, lid on but not vacuum-sealed. If you can't be sure it's bone dry, don't close it in plastic.
Sofas, beds and books
Furniture that won't go in a box needs the same thinking: clean, dry, food-free and off the floor. Vacuum a sofa first, down the sides and under the cushions, because crumbs are food. Cover it only once it's clean and dry, and raise it on a pallet or boards so it isn't sitting on the floor. Our guide to whether you can stand a sofa on its end covers positioning and covers. Mattresses and bedding follow the fabric rules above.
Books are paper, and paper is nesting material. Pack them in a lidded plastic tub, or a sound, well-taped box, and keep them off the floor. Children's toys go in the same way: cleaned first, with no sweets or snack wrappers tucked inside.
Business stock follows the same logic. Paper and card packaging is nesting material, so keep packaging and boxed stock in lidded tubs or on pallets off the floor; our business storage page covers storing stock with us. If you rely on Contents Protection for business stock, ask us for the policy wording to confirm it's covered.
Insects: moths and carpet beetles
The easiest place to stop insects is at home, before anything is packed. Before storing wool, fur, feather duvets or a rug:
- look for holes, larvae or tubular case trails, particularly on wool, cashmere and silk;
- clean it, or at least brush wool and fur, as the Museums Association guide advises;
- pack it in a closed box or garment bag once it's bone dry.
Cedar or lavender aren't mentioned in our terms, so ask us before you add them. Mothballs and chemical repellents are a different matter: our terms rule out "chemicals … or other potentially hazardous substances" (clause 18(e)) and "any item that emits fumes, or odours" (clause 18(f)), so ask us before using them in a unit.
The Museums Association's guide says an item that's already infested may be rescued by sealing it in a plastic bag in a freezer at minus 18°C for at least two weeks. Do that at home, before it comes in.
If you're storing a whole household, it's worth visiting your unit now and then, or, if you'll be away, name someone to check it for you. Our terms advise you to inspect the unit before you store and from time to time during your stay. Droppings, gnaw marks and a musky smell are the signs of mice. If you see any, tell us straight away, so it can be dealt with across the building. Please don't put down your own poison: rodent bait is a chemical, and our terms don't allow chemicals or other potentially hazardous substances in a unit (clause 18(e)). Ask us before setting traps too.
If something is damaged, who pays?
Your goods are stored at your own risk under our terms (clause 30), and they must be insured for their full replacement value the whole time they're with us (clause 31). Our Contents Protection lists "damage from moths, insects, or vermin originating externally" among the risks it covers. The page doesn't define "originating externally", so if you're relying on it for anything valuable, ask us for the policy wording when you book. If you use your own insurance instead, check it covers pest damage in a storage unit, since policies differ.
Storing with us
If you're packing a house into storage and want it to come out as it went in, get a price online or call us on 0800 2545585. Our Box Shop has boxes and packing materials for the move.
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