Underbody Coating

Underbody coating is usually applied uniformly to the undercarriage of the automobile.

It can be either sprayed or painted

The main purpose of undercoating is to prevent rust from water, road debris, gravel and small pebbles.

Underbody coating can also reduce wear and tear.

As Indian roads and climatic conditions are not predictable, we must require underbody coating to prevent our car's underbody from rust.

An image of with (protected) and without (Not protected) underbody coating -

Types of Underbody coating –

1. Rubberised under body coating
2. Wax based underbody coating
   
3. Asphalt based under body coating
   
4. Polyurethane underbody coating –

1. Rubberised under body coating

This is generally thought of as the best underbody coating for your car. It preserves the underbody well, protecting it from scratches. Applying this to the undercarriage is not much of a hassle either.

2. Wax based underbody coating –

This – more or less – ephemeral undercoating will wear away in a few months’ time. On the upside, wax-based undercoating puts up a big fight against moisture. It is also the most affordable option out there.

3. Asphalt based under body coating –

Best suited for lorries, trucks and large vehicles this provides a greater degree of protection compared to rubber-based coatings. However, asphalt-based coatings contain little amounts of rubber for sound-insulation purposes. The process of applying this coating is a bit time-consuming though.

4. Polyurethane underbody coating –

This coating closes up splits and fractures on the underbody of the vehicle. It offers up good protection against corrosion and also bonds with the metal. Unlike in the case of asphalt-based coating, you can paint over the polyurethane coating.

Pros of underbody coating –

1. Corrosion resistant – Underbody coating can come in handy especially if you live near the sea, where there is too much humidity, and rusting is just one of those everyday things. You should also seriously consider undercoating if you reside in a place where it snows in winter.

2. Reinforcement - If your car comes with stock underbody coating, using another coating on top of it, is good. It will offer additional reinforcement, protecting the underbody from water, road debris, gravel and small pebbles. There would also be a lesser chance for the factory coat to flake away.

3. Increase car's life span – Underbody coating not only prevents our cars from corrosion but also protects the engine and transmission as well! Then the life span of the car will definitely increase.

4. Absorb noise - Underbody coating not only prevent rusts , it also prevent some noise since the underbody coating is made of rubber.

Disadvantages of underbody coating –

1. It’s less helpful if corrosion is already present.
2. It works best on new cars.
3. It adds weight to vehicle. As a BIW engineer we must think to reduce weight but it is not possible to protect our car's underbody from rust with undercoating.