Modifying a car can have a huge impact upon it's insurance premium. Some modifications may have little or no effect, some may actually make the car more affordable to insure but a lot of modifications, including the most common ones, can increase the premium substantially. However you might save a lot ofmoney by seeing which insurer gives the best deal from 120+ providers online - click the button for quotes.
Why do modifications affect the cost of car insurance?
A huge amount of work goes into designing a car to make sure that it is not only comfortable and economical, but safe as well. To be safe it needs to have good handling characteristics, with the absolute minimum of oversteer or understeer, and the braking system needs to be adequate for the type of driving that the car is designed for. Even the shape of the bodywork itself is important; modern cars are tested in wind tunnels to ensure that they are not unduly affected by crosswinds, and that there is no tendency for the front wheels to lift at high speed. Modifications may affect all of these.
Do I have to inform my providers about modifications to my car?
It is absolutely really important to do so. Failing to inform them could result in a refused claim, or even a refusal to ensure you at all.
Which modifications can adversely affect the safety of the car?
Fitting a more powerful engine: anything that makes a car go faster than it is designed to do can mean that the braking system is no longer adequate. In addition, putting a more powerful engine into a car can affect the weight balance. A heavier engine in the front can cause understeer, which means at speed it can be difficult to persuade the car to go round a corner; a heavier engine in the back can cause oversteer, in which the turn into a corner can be much sharper than intended as the rear of the car slides out. In extreme cases this can cause a car to spin.
Lowering the suspension: by lowering the centre of gravity of a car it can sometimes make it more stable and improve handling. However, this can adversely affect the wheel tracking. This can cause not only accelerated tyre wear but also less area of tyre actually in contact with the road, increasing the chance of a skid.
In addition there is more chance of the underside of the car grounding, particularly if going over speed bumps, potholes or debris in the road, or when bouncing over a hump. This raises the possibility of damage to vital components such as brake pipes, fuel lines, interior sidewalls of tyres, and anti-lock braking systems.
Front lighting can be adversely affected and necessary alterations can increase the risk of dazzling oncoming cars, particularly when driving on an uneven road.
Fitting a spoiler: this can obstruct a driver's view through the rear window. It can disrupt the carefully designed airflow over the car, perhaps making it more susceptible to front wheel lift, and if it worked loose it could be a considerable hazard to other road users.
Fitting alloy wheels: it is very much encouraged that the wheel is as close as possible in size to the originals, since the car's braking system, suspension and springs were designed around this. However the major disadvantage to fitting alloys is that straightaway the car can become a target for thieves. Very often, when stealing alloy wheels from a car, the thieves do more damage to the car as well, resulting in a hefty repair bill.
Whether or not this modification would result in a substantial insurance increase would probably depend upon where you lived; if there was a history of car theft locally then a higher premium could be a distinct possibility but if it was a relatively crime free area it may make little or no difference to the premium.
Fitting an expensive sound system: if you do this then please don't make it too obvious. Get it fitted in such a way that it is not visible to a passerby and don't advertise the fact. Many a car is broken into purely because the thief knows that a sound system is easy to sell!
Fitting tinted windows: these can reduce visibility for a driver, particularly at night or during wet weather. They may even be illegal as well. There are strict limits laid down for the amount of light that tinted glass will allow to pass, particularly for the windscreen and front side windows.
Installing a sunroof: the vast majority of cars nowadays are of monocoque construction, in other words the body is part of the structure, as against a system in which a body simply sits on top of a chassis which provides most of the strength of the car. By cutting into the body it is possible to weaken it to the extent that the car can flex, making the steering system unstable, or even suffer structural failure. If you really want one make sure it is factory fitted before the car leaves the manufacturer.
Fitting a supercharger: this is really an absolute no-no. The power output of the engine is likely to be far more than the braking system, steering and roadholding was designed to handle.
Fitting a body kit: these are usually made of fibreglass, which is prone to splinter on impact, and often the front and side skirts are closer to the ground meaning more chance of damage particularly when going over speed bumps.
Having a customised paint job
Some providers are extremely wary of customised paint jobs since matching them up in the event of accident repairs can be far more problematic than on a car with a standard factory finish.
Which modifications make a car safer?
Reversing sensors: if your car doesn't already have them then fitting them can greatly decrease the risk of backing up into an obstruction or another vehicle. Similarly having a reversing camera fitted may be very helpful if your rearward vision is poor.
Immobilisers and trackers: these can help to prevent your car being stolen or at least give you a better chance of getting it back if it has been taken by a joyrider.
Which modifications SHOULD have no effect on a car insurance premium (but still might)?
Converting the engine to run on LPG: running on liquefied petroleum gas instead of petrol or diesel may save a great deal of money on fuel costs and in most cases it should make no difference to insurance prices. However this will vary from one insurer to another. Some may refuse to cover a modified vehicle at all, and others will want to know exactly what has been fitted, and by whom.
Modifications to accommodate a disabled driver: the Equalities Act of 2010 makes it illegal for an insurance company to increase a premium purely because the driver is disabled, provided that the DVLA have confirmed that that person is fit to drive. However do bear in mind that a modified vehicle may have expensive equipment fitted, such as a wheelchair lift or specially adapted braking or steering systems, and providers could be within their rights to increase a premium based on the possible extra cost of repairs in the event of an accident.
What happens if I do modify my car?
As soon as you carry out any car modifications at all you must inform your insurer. They then have the option of not increasing your premium (although you will probably get a charge for modifying the policy if it is done mid ' term); charging an additional premium or, if they consider the modification to be too extreme, they may even refuse to cover the vehicle at all. If this was to happen you could be obliged to inform any future insurer that you had had cover withdrawn, which could make it at best expensive, and at worst impossible, to get alternative insurance at anything like a reasonable cost.
The best advice to give could be to inform the insurer of what you plan to do before making the modifications, and find out what their attitude could be . If you are fitting additional safety features such as reversing sensors or antitheft devices then you might even see a premium decrease.
