Moving house? The cardboard box is a pest vehicle

Nobody inspects a cardboard box. It's the one object we carry into our homes without a thought, from supermarket stockrooms, online-retail warehouses, office clearances, friends' garages — precisely the places pests commute from. The US EPA's pest guidance names the habit directly: check packages and boxes before carrying them in, and treat cardboard clutter as prime pest harborage. A move, when dozens of boxes cross a threshold in one day, is the single biggest pest-introduction event in most households' year.

Why cardboard specifically

Cardboard is engineered to be three things pests love: dark (flutes and corrugations are ready-made corridors), warm (stacked boxes insulate), and edible-adjacent — the glue is starch-based, and silverfish, booklice and cockroach nymphs graze on it. Bed bugs don't eat cardboard, but they ride in it: the corrugations are ideal daytime harbourage within reach of a host, which is why secondhand furniture and boxes that slept in storage units are the classic bed-bug introduction route. And cardboard absorbs moisture — the damp box in a garage corner is a three-star pest hotel with no questions asked.

The moving protocol, start to finish

At packing: use plastic totes where you can — they don't harbour, and they're inspectable. Boxes that must be cardboard get sealed, not folded; open flaps are doorways. Before anything crosses the threshold of the new home: inspect on the driveway or in the lobby — torch along seams and flutes, look for egg cases (small, brown, purse-shaped along box seams), droppings (like black grains of rice), shed skins, or the tell-tale blood-and-faecal spotting of bed bugs along tape lines. The secondhand trap: that free sofa or wardrobe is the highest-risk object that will ever enter your home — inspect seams, screw holes and dust covers, or leave it. Mattresses especially: no secondhand mattresses, full stop. On arrival: unpack boxes completely and get the cardboard out of the house within days — stacked, empty boxes in a utility room are the exact clutter-harbourage the EPA warns about, and they undo the clean start.

If you've already moved the problem in

Nothing here is a diagnosis of doom — it's an inspection habit. Signs after a move (bites in a line, droppings under the sink, night-time tickling in walls) get the 48-hour protocol: identify, monitor, escalate. Caught in the first weeks, an introduced infestation is small and localised; caught after a year of "we should probably do something about that garage", it's a professional's job. The boxes were never the problem — the not-looking was.

Sources: US EPA pest-prevention guidance (check packages and boxes; cardboard as harborage; bed-bug caution with secondhand items). Reviewed September 2026 · general information.