Roof box could invalidate your insurance
02/06/2025

Motorists are being warned that common summer modifications, such as adding roof boxes, towbars and bicycle racks, could end up costing them.
According to the motoring experts at Quotezone.co.uk, failing to declare these, as well as other summer modifications including window tints and sunroofs could void car insurance policies.
They’re urging motorists to inform insurers of any changes they make to their cars as the weather warms up.
If they fail to keep their insurer up to date, motorists could be driving with a void insurance policy and if they need to make a claim, an insurer could refuse to pay out.
Summer additions including tow bars, roof boxes and bike racks can all be classed as modifications, as can window tints and sunroofs.
While adding a roof box could make travelling with families easier with the additional room for luggage, it could void insurance if it’s not updated on the policy.
The same is true for bike carriers, which are a necessity for cycling enthusiasts. This modification is seen as increasing the likelihood of damage or an accident, especially if it isn’t installed correctly.
Other more obvious changes like window tints, sunroofs and adding a towbar must also be declared, most likely as they could enhance the cost of the vehicle and increase the risk of an incident.
Greg Wilson, CEO and car insurance expert at Quotezone.co.uk said: “As the weather improves and motorists head off for summer trips, many make seasonal modifications, like adding a roof box or towbar, but failing to inform the insurer of these changes could invalidate the insurance and leave the driver unprotected.
“All the additions – towbars, roof boxes and racks, window tints, bicycle racks and adding a sunroof could all be seen as increasing the risk of an accident or the likelihood of damage, which is why it’s so important to notify the insurer.
“A recent Quotezone survey showed 65% of drivers didn’t realise a sunroof could be seen as a modification. Declaring summer modifications helps ensure your cover remains valid if anything goes wrong and you need to claim.
“There’s a full list of modifications that insurers need to be aware of, our car insurance quote form details them all with an explanation on modifications – it’s so important for drivers to check the list thoroughly as some items are quite unusual and many drivers may assume they are covered as standard.”
Quotezone.co.uk’s checklist of summer modifications which could invalidate your insurance:
Tow bars
Having a tow bar fitted to the car can potentially affect your insurance and needs to be declared to your insurer. Towing another item, whether that’s a caravan, trailer or other items, increases the risk of an accident happening. Make sure you notify your insurer before fitting the tow bar and check your policy covers the item you’re towing too.
Window tints
Window tints do not automatically invalidate your insurance if they’re legal and your provider has been informed. UK law restricts window tints on the front windscreen and front side windows. At least 75% of light must pass through the front windscreen and at least 70% through the front side windows. There are no restrictions on tinting the rear windows. Premiums are unlikely to go up with this modification but you must declare to your insurer or you could invalidate your insurance policy.
Sunroofs
While it can be a cooling feature during hot weather, adding a sunroof to a car that doesn’t already have one is considered a car modification. It can alter the car’s value, repair costs and even its structural integrity. Those added after purchase can also be prone to leaks.
Roof racks and boxes
Installing a roof rack or roof box when you’re travelling gives additional storage space for the journey. However, it can be classed as a modification and failing to declare could void your cover if a claim is made. Roof racks are not standard equipment and can impact the vehicle’s weight distribution and potentially its handling. Poorly secured or overloaded roof racks can also be dangerous.
Bike carrier
If you’re adding a bike carrier for summer adventures, notify your insurer. They are classed as modifications and may be seen as increasing the risk of accidents or damage to your vehicle, especially if they’re not properly installed.
Quotezone.co.uk helps over 4 million people every year find savings on all sorts of everyday bills and essentials such as car, bicycle and motorbike insurance.
This article is intended as generic information only and is not intended to apply to anybody’s specific circumstances, demands or needs. The views expressed are not intended to provide any financial service or to give any recommendation or advice. Products and services are only mentioned for illustrative rather than promotional purposes.