Roof boxes are a great way of creating extra packing space when you’re setting off on a long drive or for a summer getaway. We want to help you maximise this extra space and really get the most out of your roof box, so here are our top tips for loading your box and making sure the contents are secure.

1. Know your weight limits

All roof boxes have a maximum weight that it’s safe for them to carry. As these weights tend to range from around 50kg to 75kg depending on the size of your box, it’s unlikely that you’ll need to worry about overfilling them, but it’s still useful information to have in mind. If you’re not sure what the weight limit is for your roof box, you’ll usually be able to find this information on the product page or in the accompanying documentation.

It’s also important to be aware of the weight limit of the roof of your car, as well as the capacity of your roof bars, as sometimes these can be less than the roof box can hold (both of these can usually be found in the relevant manuals).

Finally, keep the total weight capacity of your car in mind when you’re loading it up (again, your vehicle manual is usually the place to go for this info) and make sure that you take the weight of the bars and box into account.

2. Pack the heaviest items in your car

It’s still a good idea to pack the heaviest items in your car first, particularly if you’ve got a good-sized boot because your car is always going to have a greater weight limit than your roof box.

Just make sure that you keep the height of what you’re packing to a reasonable level so that you still have an unobstructed view out of your back windscreen. Once you reach this point, it’s time to start loading the roof box instead.

3. Spread the weight evenly

This is our last point about weight, we promise! But it’s a pretty important one because if you don’t spread the weight in your roof box evenly then you run the risk of creating an uneven ride and potentially a noisy one too, as items slide around.

We’d always recommend putting the heaviest items in the centre of your roof box and balancing the weight out as much as possible.

4. Put your suitcases up top

While you might assume that suitcases belong in the boot and items that aren’t so neatly packed belong in the roof box, the truth is that many roof boxes are designed in a way that makes them ideal for storing suitcases. In fact, you could almost see your roof box as a much larger suitcase that just happens to be attached to the roof of your car!

If you have a couple of smaller suitcases, they’ll probably be able to fit neatly side-by-side in a roof box, leaving room for other items while helping to stop everything from sliding around. A larger suitcase could play the same role, fitting comfortably while helping to anchor other items in place. It’s all about maximising your packing space and leaving no space unfilled!

5. Or put the awkward items there instead

If you’ve got some awkwardly-shaped items, like sports equipment, camping furniture, or a tent, then a roof box can be the perfect home for them. Rather than cramming them into your boot or poking them between the seats to get them to fit, you can give them a dedicated space of their very own. And as they’re unlikely to be items that you’ll need during the journey, you can also free up essential in-car space for the ones that are.

6. Make sure your roof box is properly secured

This is kind of an obvious one, but the last thing you want is your roof box flying off during your journey so it’s really important to ensure that both your box and roof bars are fitted correctly and securely. The two most common mounting systems for roof boxes are u-shaped bolts and power click mounts. Fitting instructions are included in your product documents.

If you’ve just bought a roof box or you can’t quite remember how to fit yours correctly, then the colleagues at your local Halfords store will be happy to help. Not only will they fit the roof box for you for a small fee, but they’ll demo the process so that you can do it yourself next time.

7. Secure your locking system too

Another thing that it’s essential to secure is your locking system – or it could be the contents of your roof box that goes flying, rather than the box itself! When you’re filling up your box, make sure that you’re aware of where the closing and locking components are, and that they’re not blocked or obstructed in any way by your belongings. Then ensure that everything is firmly locked up before you leave on your journey.

If you have lost your keys to the roof box, you can purchase spare keys directly from Halfords. Simply locate the number on your key barrel and search via our roof box accessories page. We also have various key barrels available to purchase:

8. Take advantage of straps, hooks and holders

Your roof box is likely to have various straps, hooks and holders on the inside to help you secure your items, so make the most of them. Like with suitcases, they can be used to pack everything down neatly and maximise space or store specific items that you don’t want to be able to rattle around in the confines of the box.

You can view our range of bungees and tie-downs via our roof box accessories page.


If you haven’t invested in a roof box yet, then we’re here to help. We stock a great range of high-quality roof boxes from top brands and our handy roof box finder means you can easily narrow down your options until you find exactly what you’re looking for.

You can also book a fitting appointment online – simply select the fitting option during the checkout process, then pick a date and time that suits you. Or if you’d prefer, pop into your local Halfords store and speak to one of our colleagues.

With the uncertainty of the energy price cap and cost of living crisis, we know that you’ll be keen to save money as and when you can. Here at Halfords, we’re committed to driving down prices and offering you the best value possible to keep you safe, happy, and secure. We’ve pledged to never be beaten on price on 1000s of motoring essentials – read more here.