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How to Regularly Clean Fiberglass RV Siding and Deal with Oxidation

Fact checked by Ronal Dowens

How to Regularly Clean Fiberglass RV Siding and Deal with Oxidation

If you’re a traveler like me who uses recreational vehicles, then it’s pretty normal for you to encounter various environmental conditions. These can be the sun’s heat, the polluted air, a splash of mud, or even waste from human activities. Fortunately, RV sidings are here to help protect you from such elements.

RV sidings are commonly made of fiberglass, and they’re said to be more durable than their aluminum counterpart, regardless if they’re either the smooth or corrugated type. However, even though they provide better insulation and more dent resistance, their surface is still prone to stains, fading, and oxidation. To help you practice regular maintenance, here are some essential steps you want to follow regarding how to clean fiberglass RV siding on your vehicle.

Things to Know and Prepare


Oxidation in the fiberglass siding of an RV appears as a cloud-like appearance on its surface, making it more translucent. This is due to the reaction of the gel raisin coating (which is responsible for the glistening finish) and the extreme changes in temperatures in the environment.

The more the fiberglass is oxidized, the less effective it will be. There are industrial restoration jobs that bring back its clearness for a while, but nothing beats a regular cleaning to keep it well-maintained. To do that, here are the things you will need:

Protective equipment:

  • Rubber gloves, or any gloves used for washing clothes

Cleaning aids:

  • Broom
  • Wiping cloth
  • Sponge
  • Ladder

Cleaning agents:

  • Liquid laundry detergent
  • Bug and tar remover, or if an alternative is needed, WD-40 is a good example
  • Fiberglass wax
  • Methyl ethyl ketone (MEK), which is used for coating solvents, or acetone as an alternative

How to Clean Fiberglass RV Siding Instructions


Step 1: Preparatory Cleaning

Given that you have worn the proper equipment, you will now have to sweep the surface for any debris including the roof. Although the RV siding is the target for maintenance, it will be efficient to include the roofing, especially if it is covered with fiberglass. Utilize the ladder to reach high areas.

Step 2: Stain Removal

When your RV has gone to trips closer to nature, chances are there will be areas that are affected by bugs or any secretions from the wild. To remove this, use a bug and tar remover that is safe to be used on fiberglass.

They can be easily purchased at any of the auto parts store or RV-dedicated supply stores. If removal is in need, a WD-40 can be an ample substitute.

Step 3: Washing

After the removal of stains and secretions, begin washing by soaking the sponge to a soapy solution of liquid laundry detergent and a gallon of water. Start applying from the topmost part all the way to the bottom of the siding.

As more dirt is collected, re-soak the sponge and resume applying. Don’t scrub if the sponge you are using has a scrubber. Rinse the detergent solution with another set of water or just use the garden hose for easy targeting.

Step 4: Waxing Preparation


When the surface has been washed up, it is time to use the solvent. If possible, use rubber gloves in handling to prevent unwanted irritation when exposed to the liquid.

The MEK is an efficient solvent on surface coatings. They can be purchased on any large stores for home improvement solutions or any RV-focused stores.

Soak the wiping cloth with the MEK and wipe all surfaces possible. For greases and oils where the detergent solution can’t be removed, apply as much amount of MEK as needed. You will see that the cloudy-like appearance is beginning to be more transparent.

Step 5: Waxing

As the oxidation removal process is finished, make sure to wipe the entire surface. This is to make sure that the wax to be applied will definitely be absorbed by the RV’s exterior.

After that, begin applying the fiberglass wax purchased in accordance with the manual’s instructions. The wax will restore the glistening finish your RV used to have. You will know when you are done if the expected results are met.


The said instructions can be very effective on sidings with mild oxidation. For larger damages, there is a process called “wet buffing” in which the surface is buffed to its former state. Also, make it a habit to do the maintenance regularly once a month at most.

The RV fiberglass siding is expensive compared to the aluminum one. It is only logical to maintain its appearance to continue having its effectiveness against the elements of nature. Anyway, hope you find the answer to the question of how to clean fiberglass RV siding. If you have enjoyed this tutorial, feel free to react and express your opinions in the comments section.

For more information about anti-oxidation and cleaning, please take a look at a detailed guide to removing oxidation from RV decals and removing stains from RV awnings.

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