Packing your car for a comfortable family holiday

Start with weight, not volume

The most common mistake families make is packing the boot like a wardrobe: everything stacked to the roofline simply because it fits. A fully loaded car behaves quite differently from the one you drive to the shops, and where the weight sits matters far more than how neat it looks. Put the heaviest items as low and as far forward as you reasonably can, ideally over or just ahead of the rear axle. Suitcases, tinned food, a box of wine for the cottage and that toolbox you insist on bringing all belong at the bottom of the load bay, not balanced on top of a soft holdall.

Keep light, squashy things — coats, pillows, beach towels, sleeping bags — for the upper layers, where they can fill gaps without pushing the centre of gravity upwards. If you're using a roof box or a rear-mounted bike rack, the limits are in your handbook and they're lower than most people assume. Roof boxes typically max out at 50–75kg including the bars, and towbar nose weights are usually in the same range. There's also a gross vehicle weight you must not exceed, and a family of five plus a full tank of fuel eats into that allowance quickly. If you suspect you're close, weigh the bags on the bathroom scales before they go anywhere near the car.

Secure anything that could become a missile

A five-kilogram suitcase in an emergency stop at 50mph carries the force of a small motorcycle. That's the whole reason nothing loose should be left free to slide, tumble or launch itself forwards. Use the load-bay tie-down points many estates and SUVs come with, or a simple cargo net stretched across the boot floor. Restrain bulky items with luggage straps rather than hoping friction will do the job.

• Never stack luggage above the height of the rear seatbacks if you can avoid it — it blocks your mirror and becomes a projectile.
• Keep the rear headrests raised. They're a restraint, not decoration.
• Don't use the parcel shelf as a storage shelf. It's designed to hide the boot, not carry weight.
• On the back seats, seatbelts should be fastened across any bulky item, and nothing heavy should sit in the middle where it can slide into the front.
• Small, hard objects — a travel kettle, a tablet in a rigid case, a thermos — should go in a closed bag or under a seat, not on a lap.

Adjust the car before you turn the key

A loaded car needs different settings. Check your handbook for the fully loaded tyre pressures, which are often a few psi higher than the everyday figures, and inflate them when the tyres are cold. Under-inflated tyres on a hot motorway run are a genuine blowout risk, and over-inflated ones ruin the ride for everyone in the back.

Use the headlight levelling dial to drop the beam so you're not dazzling oncoming drivers. Top up the screenwash — summer motorway driving plasters the windscreen in insects — and check the coolant and oil while the bonnet is up. Clean the rear window and mirrors properly; with a full boot, your rear view is already compromised, so make what's left of it count.

Build a cabin that still works at hour three

The difference between a pleasant drive to Cornwall and a miserable one is usually decided by what's within arm's reach. Keep snacks, water and entertainment in the cabin, not in the boot, and keep them organised so you're not rummaging one-handed at 70mph.

• Fill reusable bottles before you leave. A flask of hot water and a couple of mugs is a small luxury on a cold morning.
• Choose snacks that survive heat and don't crumb everywhere: oatcakes, nuts, dried fruit, plain biscuits. Chocolate and anything with a soft icing is a mistake in July.
• Pack a small bin bag or a collapsible car bin, plus a pack of wet wipes and a roll of kitchen paper.
• Download playlists, audiobooks and episodes before you go. Signal in parts of Wales, the Lakes and the Highlands is patchy at best.
• Bring a charged power bank and a spare charging cable. One cable always fails.
• For younger passengers, a lap tray, magnetic travel games and a couple of new paperbacks work far better than a single tablet with a flat battery.

Keep the day bag and essentials accessible

Buried luggage is the enemy of a calm departure. Pack one bag that stays in the footwell or under a seat: suncream, sunglasses, spare nappies, medicines, antihistamines, plasters, a phone charger, the ferry or campsite paperwork, and any booking confirmations. If you arrive late at your destination, you want an overnight bag you can carry straight in without unloading the whole car in the dark.

Make sure your breakdown kit is present and reachable: warning triangle if you're travelling abroad, high-visibility vest for each occupant, a torch, a first aid kit and jump leads. A reflective vest stored under three suitcases is useless.

Plan the stops and pack for the last mile

On a long run, aim for a proper break every two hours or so, and treat it as part of the timetable rather than an interruption. Motorway services are convenient but pricey; a lay-by with a flask and a football is often better for everyone's mood. Book nothing so tightly that a single delay ruins the day.

Finally, leave the waterproofs, a picnic blanket and a bag of snacks near the top of the load, because the moment you arrive, someone will want the loo, someone will be hungry and it will probably be raining. A car packed with a little thought gets you there with everyone still speaking to each other — which, on a family holiday, is most of the battle won.