The fastest way to pest-proof garage storage is to close every gap a rodent could squeeze through, move everything into chew-resistant containers, and lift storage off the concrete. Add a monitoring trap or two along the walls and you've covered the fundamentals. This guide gives you the checklist, the materials, and a practical option if your garage or car park doesn't give you much room to work with: The Kookaburra, an all-steel over-bonnet unit built for exactly this problem.
Work through these in order. The first two take minutes; the rest need a bit more time or a trip to the hardware shop.
Wear gloves and a mask if you're clearing an area that already shows droppings. Old rodent nesting material can carry pathogens, so treat any cleanup as a hygiene job, not just tidying.
Rodents don't need much room. Mice squeeze through gaps around the size of a dime, and rats can get through openings of roughly 12mm — smaller than most people assume. That's why a quick glance at the garage door isn't enough; you need to check every possible entry point methodically.
Work through this list with a torch:
For anything smaller than a golf ball, steel wool or copper mesh packed into the gap and sealed over with silicone or hydraulic cement holds up far better than expanding foam, which rodents chew through easily. For larger holes, fasten galvanised hardware cloth over the opening and seal the edges. Don't forget the interior door: a heavy-duty door sweep on the garage-to-house entry stops anything that does get in from reaching your living space.
Pro Tip: Check seals from outside at dusk with the garage light on. Any daylight leaking through a gap is a gap a mouse can use.
Cardboard boxes are the worst possible storage choice in a garage. They're soft enough to chew through in seconds and they double as nesting material once torn open. Thin polypropylene tubs aren't much better in an unheated space, since repeated temperature swings make that plastic brittle and prone to cracking at the corners.
For genuine pest resistance, look at:
Keep an eye on gasket wear. A cracked or perished seal defeats the purpose of a gasketed bin just as surely as no lid at all.
Clutter is what gives rodents somewhere to hide undisturbed, so layout matters almost as much as container choice.
If your garage is genuinely tight on floor space, a wall-mounted or raised system is often the better fix. Ideas from home organisation specialists can help you plan shelving that keeps everything accessible without giving pests somewhere to nest behind it.
Monitoring is what tells you whether your sealing and storage work is actually holding. Place a few snap or catch traps along the walls, in corners, and near any suspected entry point, even if you haven't seen any activity yet. An untouched trap after a month is a good sign; a triggered one tells you exactly where to focus your sealing effort.
Natural and chemical deterrents (peppermint oil, ultrasonic devices, commercial repellent sprays) can make a garage less appealing, but they only work as one layer among several. None of them stop a determined rodent from entering through a gap that's still open.
Watch for these signs of active infestation:
If you're seeing two or more of these at once, pest-proofing is genuinely a combined effort of sealing, decluttering, and monitoring together. That's usually the point to call a licensed pest controller rather than keep adding traps.
Pest-proofing isn't a once-off job. Seals wear, weatherstrips perish, and new gaps open up as a building settles.
That log matters more than it sounds. If activity reappears in the same spot six months later, you'll know immediately whether it's a repair that failed or a new access point.
Not every garage or car park lets you seal, shelve, and monitor the way this checklist describes. Apartment car parks and shared garages often rule out permanent changes altogether, which is exactly the gap that The Kookaburra was built to fill.
It's an all-steel, three-point locking, corrosion-resistant unit mounted above your car bonnet rather than on the floor, holding up to 500kg while keeping everything inside a lockable steel shell.
Pro Tip: If you're renting or living under a body corporate, ask about approval support before buying any storage upgrade. Approval support is often handled as part of the purchase process for units like The Kookaburra.
Repellents have a place in a pest-proofing plan, but only as a supporting layer, never as the main defence. Peppermint oil, cedar blocks, and commercial ultrasonic devices can make a garage less attractive to rodents, and some tenants use them as a first line before committing to sealing work. None of them close a gap, though, and none stop a mouse that's already found a way in.
If you're using sprays or granules near stored goods, check the label for safety around food, pet supplies, and anything you'll later bring into the house. Products marketed for outdoor perimeter use aren't always rated for enclosed, poorly ventilated spaces like a garage. Peppermint oil and similar natural options are generally low risk around storage, but they need reapplying often, since the scent fades within days in a space with any airflow.
Chemical rodenticides carry a different risk profile again. They're effective at reducing an existing population, but bait stations need careful placement away from pets and children, and a dead rodent inside a wall cavity creates its own smell problem for weeks. For most home garages, a combination of sealing, gasketed containers, and monitoring traps solves the problem without needing bait at all. Save rodenticide for cases a licensed pest controller has actually assessed, rather than reaching for it as a first response.
Whatever repellent you choose, treat it as maintenance, not a fix. Reapply on the same schedule you use for checking seals and traps, and don't let a can of spray under the shelf replace an actual gap repair.
A clean garage is a less interesting garage, from a rodent's point of view. Food residue, spilled fuel, and damp cardboard all send signals that there's something worth investigating, so cleaning routine is as much a pest-proofing tool as any seal or trap.
Start by clearing the floor completely once every few months rather than working around what's already there. Sweep up any crumbs, birdseed, or pet food spillage immediately, since even small amounts left overnight can attract activity. Wipe down shelving and the base of bins with a mild disinfectant, particularly in corners where dust and debris build up unnoticed.
Damp cardboard and old newspaper are two of the biggest offenders. They soak up moisture, break down into soft nesting material, and rarely get noticed until something's already living in them. Bin anything cardboard that's been sitting on the floor and hasn't been checked in months, and replace it with a sealed container if you need to keep whatever was inside.
If you've had a confirmed rodent problem, clean up droppings and urine with a disinfectant spray rather than dry sweeping, which can spread particles into the air. Ventilate the area while you work and wear gloves. Once the area's clean, that's the moment to do a full seal check, since an active problem usually means there's still a gap you haven't found.
Prioritise three things: seal the garage door threshold and the interior door sweep, move food and animal feed into metal or HDPE containers, and clear a path along the walls so you can actually see problem areas. Bigger jobs like new shelving or a professional inspection are worth budgeting for separately. If you're already seeing droppings or chew marks, don't try to solve it with sealant alone. That's a call-a-professional situation, not a weekend project.
— Matt
Storagenest is the practical answer for anyone who's just read this checklist and realised their garage or car park doesn't give them room to shelve, seal, and monitor the way it describes. If you're renting, living in an apartment, or sharing a car park under body corporate rules, you often can't alter the garage at all, which is exactly where an over-bonnet unit earns its keep.
The Kookaburra maps directly onto the checklist you've just read. It's all-steel, so chewing is off the table. It mounts above your car bonnet rather than on the slab, so it's off the floor by design. Three-point locking steel panels and a corrosion-resistant build handle the same temperature and moisture swings that make HDPE the smarter material choice over polypropylene. And it holds up to 500kg, enough for tools, seasonal gear, and anything else you'd otherwise be storing in cardboard on the ground.
Start with a fit check to confirm it suits your bay height, then book professional installation, usually done in under two hours. You can buy outright, finance through buy-now-pay-later, or rent from $25 a week if you'd rather not commit upfront. Check The Kookaburra's specifications and see whether it fits your bay.
Metal bins and gasketed HDPE containers with a silicone seal give the strongest protection, since HDPE resists brittleness that plagues thinner plastics in unheated spaces. Avoid cardboard entirely, since it's both chewable and a nesting material.
Mice can't chew through steel, and they struggle badly with thick HDPE plastic. Thin polypropylene tubs and any cardboard offer little resistance at all.
Not through the metal itself. Mice can still get in through a poorly sealed lid or a gap around a latch, so check that seals and closures sit flush every time you use the container.
Gasketed, latching plastic boxes with a silicone gasket around the lid block dust and small insects effectively when the gasket stays intact. An all-steel unit like The Kookaburra has no gasket to wear out, and closed steel panels give rodents nothing to chew through.
Check seals, lids, and corners for droppings or chew marks monthly, and do a deeper inspection of vents and weatherstripping each season. Consistent checking is what makes sealing and container choices hold up over time, rather than any single fix on its own.