Have you ever been driving down the road and heard a car coming from a distance because of its excessive noise? Or have you been pulled over by the police because your car's exhaust was too loud? That's because there are limits to the amount of noise that vehicles can make on public roads.

In this blog post, we'll explore the topic of car noise and discuss what is considered too loud, the potential consequences of driving a noisy car, and what you should do if you own a loud vehicle.

How is a car's noise measured?

Car noise is measured in decibels (dB), a unit used to express sound intensity. The most common device used to calculate car noise is a sound level meter (SLM). An SLM device consists of a microphone and a meter that displays the sound pressure level in decibels.

To measure the noise level of a car, the SLM is placed at a specific distance from the vehicle's exhaust pipe, typically at a distance of 0.5 metres. The engine is then revved up to a specific RPM (usually around 3,000 RPM) for a set period (typically a few seconds). The SLM measures the maximum noise level in decibels.

What is the legal noise limit for a car exhaust in the UK?

The Motor Vehicle (Construction and Use) Regulations 1986 lay down maximum permitted noise levels from exhausts, and these regulations are enforced by the police and the Driver and Vehicle Standards Agency (DVSA).

In the UK, the maximum legal noise level for a car's exhaust system is 74 decibels when measured from a distance of 0.5 meters from the exhaust pipe. This limit applies to all types of vehicles, including cars, motorcycles, and commercial vehicles.

The legal sound limit for all new cars is 72 decibels (dB). This threshold is set to further reduce to 68 dB from 2026. All vehicles manufactured from 2016 onwards need to follow these noise levels.

What does the law say about car noise?

Modifying the exhaust system to make a vehicle noisier after it has been 'type approved' (checked it meets environmental and safety standards) is illegal. The police can also act if your vehicle's silencer doesn't work the way it was designed to, or if you're driving in a way that creates too much noise.

What are the consequences of having a noisy car?

It's worth noting that the police can issue a fixed penalty notice or a court summons for excessive noise from a vehicle's exhaust system. If your car is found to be too loud, you could face a fine, penalty points on your driving license or even a court appearance. Therefore, ensuring your vehicle's exhaust system is in good condition and not excessively loud is essential.

Insuring a noisy car

There is no specific car insurance policy for loud cars in the UK. However, if your vehicle is modified to increase its performance or noise levels, you may need to disclose these modifications to your insurance company. This is because modifications can affect the safety and performance of your car and may increase the risk of accidents, which could impact your insurance premiums.

Furthermore, the authorities may fine you if your car is excessively loud and violates noise regulations. This could also affect your insurance premiums, as insurance companies consider driving offences when calculating premiums.

It's important to note that you should always disclose any modifications to your insurance company, even if they do not affect the noise levels of your car. Failing to do so could invalidate your insurance policy and leave you without coverage in the event of an accident or theft.