The best roofbox is the one that fits your car and carries what you need. Bigger is not automatically better: the box’s shape, usable space, weight allowance and access to your boot all matter.
At Welwyn Roofbox Hire, we help you choose a suitable Thule setup, fit it for you and show you how to use it. Here are the main things to consider before booking.
1. Start with what you need to carry
Think about the luggage that will not comfortably fit inside your car. Clothing, bedding and other lighter, bulky items are often good candidates for the roofbox.
Soft bags make better use of the available space than rigid suitcases. If you need to carry a pushchair, tent or another large item, measure it and include the dimensions in your enquiry.
Tell us what you need to carry, rather than feeling you must choose a particular roofbox before contacting us.
2. Check the fit for your particular car
The roofbars, feet and fitting kit must be compatible with your vehicle. Roof rails alone do not establish compatibility, and equipment that fitted a previous car may not fit your current one.
Send us your registration number, make, model and year. Mention any existing roofbars and provide their model details if you know them. We’ll check whether a suitable Thule fitting system is available.
The roofbox also needs to work with the bar positions and the shape of your car. We consider its position and tailgate clearance, and explain any restriction on boot opening before you commit to the setup.
3. Look beyond the capacity in litres
A litre figure describes volume, but it does not tell you whether a particular suitcase or pushchair will fit. Two boxes with similar capacities can have different lengths, widths and internal shapes.
Long items need sufficient usable internal length. Bulky items need enough width and height, with room for the lid to close properly. External dimensions are not the same as usable internal dimensions.
Our guide to roofbox capacity explains this in more detail. You can also browse our photo gallery to see fitted setups.
4. Check the weight allowance
The amount of luggage you can carry depends on the limits for your vehicle, roofbar system and roofbox. The lowest applicable limit governs the load.
Your car’s roof-load limit includes the bars, fitting equipment, roofbox and contents. The equipment’s own weight must therefore be deducted before working out the allowance for luggage.
A box rated to carry 75kg does not automatically give your car a 75kg luggage allowance. Follow the vehicle handbook and the instructions for the equipment fitted.
Read Thule’s roof-rack load guidance, or ask us if you need help understanding the limits for your setup.
5. Consider opening, locking and loading
Our hire roofboxes open from either side, giving you more flexibility when loading and unloading. Choose the side that is safe and practical for where you have parked.
The roofbox and roofbar fitting system have locks. At fitting, we demonstrate how your particular box closes and locks, and how to secure the contents with the supplied straps.
A lock is useful protection, but it does not replace checking that the lid is properly closed or arranging insurance for the equipment and your belongings.
6. Plan for the extra height
We measure your car’s overall height after fitting and give you the figure to use when checking clearance.
Consider car parks, garages and accommodation entrances, as well as any ferry or LeShuttle booking. If you need a height estimate before fitting, ask when you enquire. Check your travel operator’s current requirements and declare the roofbox and vehicle height as requested.
7. Leave fitting and removal to us
Your roofbox hire includes compatible Thule roofbars and fitting kits where needed, as long as Thule makes a suitable system for your car, together with professional fitting, removal and a demonstration.
Please leave the fitted equipment in place during your hire. If your plans may require removal or refitting, discuss this with us before booking so we can advise on the practicalities.
If a roof-mounted setup does not suit your car or what you need to carry, ask us about alternatives. A towbar cargo carrier may be an option where the vehicle and towbar are compatible.
See the equipment in use
These videos provide an additional introduction. Features vary between models; at your fitting appointment, we demonstrate the equipment supplied for your hire.
Let us help you choose
Send us your car details, hire dates and what you need to carry. We’ll recommend suitable options available for your trip.
Request your personalised quotation — we’ll reply in less than two working hours.
You can also view our guide prices, search our FAQs or call 01438 289030.
Advice from Nigel, Owner of Welwyn Roofbox Hire.
Based on our experience helping customers choose suitable Thule equipment and professionally fitting it for their cars and journeys.
Updated October 2026.