A Beginner’s Guide to Car Soundproofing

Modern car manufacturers save money on things like soundproofing, which results in drivers constantly hearing tire and engine noise, or even wind noise. Fortunately, factory flaws are easy to fix. However, this takes a lot of time.

Noise in the car can disturb and tire not only people with sensitive hearing. Even when driving at speeds below 55 mph, it becomes extremely difficult to withstand the sonic combination of tires, wind, suspension, and engine. What to say when it comes to long trips? Unfortunately, the louder inside the vehicle, the more the manufacturer saved on soundproofing.

The problem isn’t limited to cheap cars or so-called budget brands. Noise can also appear years after the car has been started or after an accident, so the history of salvaged cars for sale is checked against the vin code before they get to the new owner, at least vin-check can help in cases where the owner was forced to seek engine repairs. Buyers of popular SUVs with large wheels and wide tires struggle the most with noise, which is one of the biggest sources of annoying hum.

Why Might It Be So Noisy in a Car?

Modern soundproofing is not only a matter of cutting the vehicle’s manufacturing costs and shortening production times. It’s also a reduction in vehicle weight, which affects driving performance, fuel consumption, and emissions. So, automakers take their benefits here.

Nowadays, a very thin lining is usually used. In sensitive areas, thin strips of solid mass are still applied to reduce the resonance of the metal coating. Along with that, large areas of sheet metal, for example, wheel arches, are covered with plastic, as a result of which a vehicle turns into a huge resonant box.

Possible Soundproofing Issues

The scale of the problem is evidenced by the interest in noise reduction services offered by car service centers. It sometimes takes several weeks to get an appointment with a specialist. Often, it’s needed to wait for materials.

The soundproofing of a car isn’t as difficult as it may seem. With a little practice, you can fix the flaws in the vehicle by yourself. The main problem with the cabin noise reduction is that you should remove almost the entire interior trim for soundproofing. For those who don’t have experience in disassembling doors and dismantling the automobile’s ceiling and seats, it’s better not to experiment but to visit a professional service center. Otherwise, it is easy to damage the clips or even break the plastic elements of the upholstery.

How to Start Soundproofing a Car

It’s clear that the thicker the materials for noise isolation, the better the effect, but don’t forget that the interior will need to be assembled back together and all fasteners and nodes should also fall into place. If you make the floor too thick, you simply won’t be able to reattach the upholstery. Also, don’t forget that the screw holes cannot be sealed, otherwise the reassembly won’t work. We also recommend cleaning and degreasing the surface before applying the vibration isolation coverage.

Soundproofing of the Wheel Arches and Underbody

Many vehicles, especially SUVs, suffer the most from tire noise. Therefore, it’s best to start soundproofing with wheel arches. Access to them depends on the car model. However, it’s generally more difficult to soundproof the front part due to the large number of electrical components and the lower mounts of the dashboard itself. At the rear, it’s sometimes necessary to disassemble the seats, trim under the trunk floor, and seat belt braces. If possible, you should cover the entire metal structure with vibration isolation coverage and then with foam noise isolation material.

Strong wind noise or suspension hum can be eliminated by soundproofing the entire floor. Unfortunately, the entire carpet will have to be removed, which means removing the seats, center tunnel, door sills, and wheel arch covers.

Car Roof Soundproofing

A poorly insulated roof produces a lot of wind noise, especially when driving on the highway, as well as the characteristic sound of drops hitting tin during heavy rain. Unfortunately, access to the metal surface of the roof is not so easy. Sometimes you can just lower the headlining without having to remove it from the passenger compartment, but then thorough cleaning and gluing of the surface will be more difficult, so it’s recommended to first remove the roof sheathing completely, carry out soundproofing work, and then put the sheathing in place.

Soundproofing of the Spare Wheel Niche and Trunk

In many SUVs, it’s the spare wheel niches and wheel arches that cause the most hum in the cabin. If space permits, it’s better to use thicker mats and as thick foam as possible. After soundproofing, the foam shouldn’t protrude (if so, then the floor with the carpet in the trunk will rise), as well as the spare tire. 

By the way, some auto owners reduce noise in the trunk with styrofoam, which is filled with foam. This method is actually very effective, but here you need to understand that this type of insulation takes up a lot of space in the trunk.

The Bottom Line

You can independently soundproof the entire interior of your car. However, we recommend going to a specialized service center. In this case, the risk of damaging the interior components is reduced to zero. It’s also easier to select suitable materials there to avoid problems with the installation and assembly of the vehicle interior.

Good modern soundproofing materials can perform many functions nowadays. In addition to noise isolation properties, they often have thermal and even anti-corrosion features. All this means that they significantly improve driving comfort.