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How to Clean Fiberglass RV Siding? – 3 Easy Ways

Written by Philip Lopez / Fact checked by Paul Lemaire

how to clean fiberglass rv siding

Too much exposure to the sun can fade the glossy fiberglass exterior. The oxidation definitely looks horrible with the chalky spots on the surface. To prolong the life of your RV, you need to learn how to clean fiberglass RV siding.

You can wash it with soap and water or use a gentle car wash. Remove oxidation with a special solution or use a buffer. To restore the gloss, consider using wax.

Here’s what you can do to restore the shine on the outside of a camper trailer.

Table of Contents

Method 1: Homemade Wash


Light dust, dirt, and grime are easily cleaned with water and some soap. If you spot streaks of tar and sap, you can use a stiffer brush.

What To Prepare

Step 1: Wash With A Homemade RV Wash Solution

  • Scrub the sidings with a soft-bristle brush to remove dust and other debris.
  • In a bucket, fill it with water and liquid laundry detergent. Alternatively, you can mix two gallons of water with a cup of white vinegar.
  • Wet a sponge with the homemade cleaning mixture and wipe the exterior.
  • Start washing from the top down to keep the drippings out of an already clean surface. For hard-to-reach areas, use a wash glove.

Watch how to wash your fiberglass RV sidewalls in this video.

Step 2: Rinse And Dry

After cleaning, rinse to reveal the results.

  • Rinse the soapy areas with a garden hose. Be wary of blasting high-pressure water on sensitive parts, like silicone sealants and rivets, because it can cause damage.
  • If you see some stains left, use a short handle brush with hard bristles to remove them. Scrub until the RV exterior is blemish-free.
  • Wash again to remove any soapy residue, then dry with a clean rag or towel.

Method 2: RV Exterior Cleaner + Wax


Some regular soap might remove the special coating on the RV and leave a film, so invest in a good fiberglass camper cleaner.

What To Prepare

  • Car wash cleaning concentrate
  • Oxidation remover
  • Bucket of water
  • Sponge or soft-bristle brush
  • Microfiber towels
  • Cotton cloths
  • Garden hose
  • Gloves
  • Wax

Step 1: Wash The Sidewalls


Before you apply the cleaner, rinse the RV exterior to loosen any dirt and debris. This will make the job of the cleaner a lot easier in removing scum, grime, and other organic material.

  • Mix the gentle cleaner concentrate with a bucket of water according to the product’s instructions.
  • Apply the cleaning solution to the fiberglass exterior with a sponge or brush. Work on one side, then rinse with a garden hose downward.
  • Wipe or scrub the next side, then rinse again thoroughly.
  • Dry with a soft towel.

Step 2: Remove Oxidation

Some hazy parts might still be left on the surface, so you may need to use an oxidation remover. You want them gone before you apply the wax.

  • Wear gloves to protect your hands from irritation.
  • Wet a cotton cloth with some of the oxidation remover solution and rub on all affected areas of the fiberglass sidewalls. Avoid wiping on rubber, cloth, or vinyl surfaces because the chemicals may damage them.
  • Immediately wipe with a separate cloth to dry. You’ll notice that the hazy-like appearance will start to disappear.

Step 3: Apply Wax


Waxing fiberglass RV is the next step to reviving its shine. I use ceramic wax for fiberglass RV because it efficiently fills the pores, making it look new again.

  • Get your bottle of wax and shake it up to prevent separating the ingredients.
  • Wet your large sponge a bit and drizzle on it an adequate amount of wax.
  • Apply the wax gently to the surface. Work it around the RV, going with the grain.
  • Fiberglass tends to be quite absorbent, so use a little more wax.
  • Once done, wipe the surface with microfiber towels.

Method 3: One-Step Compound


If your RV has heavy oxidation, you can use a power tool. It will also be a lot easier if you use a one-step compound to save costs of buying a separate cleaner and wax.

What To Prepare

  • Clean and gloss one-step compound
  • Power buffing tool
  • 100% wool pad, medium size
  • Cloth

Step 1: Apply The One-Step Compound

Instead of using two products to cut through the oxidation and polish RV surfaces, we’ll be using a single product to save time. The results may also be far better than any fiberglass RV cleaner products.

  • Get your buffer and replace the foam pad with a wool pad. Wool pads are more effective than foam pads in removing oxidation because they have that slight fine grit.
  • Swirl the one-step compound onto the wool pad.
  • Get ready to apply the compound onto the fiberglass RV siding surface, paying more attention to the oxidized spots.

Step 2: Buff The Oxidized Surface

Now, it’s time to buff the oxidized parts away. You need to be careful during this part because you don’t want to strip the finish of your fiberglass siding.

  • Set the power buffing tool to the lowest setting and spread the compound over the surface evenly.
  • Work around the siding area, keeping away from decals.
  • Once you can’t see any clumps of the compound, slightly increase the buffer’s speed to smoothen the surface until the compound is all gone.
  • Finish with a clean cloth to remove any residue and light swirl marks.

Additional Tips

  • Park your RV away from direct sunlight when you clean a fiberglass camper.
  • Clean in sections. Wash and rinse on one side and repeat on the other side.
  • To make cleaning and waxing easier, use ladders to access far-to-reach areas and a cart to store all the products.


As you can see, learning how to clean fiberglass RV siding is quite easy. You just need to be gentle and use the right cleaning or waxing products to get the best results. Wash with soapy water or use a gentle car wash, it’s your call.

Let us know your thoughts about these cleaning methods. If you find the article helpful, please share this with your friends.

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