3-Step Guide For Repairing Small Dents In Your RV’s Fiberglass Body

If you were recently involved in a minor collision with your RV, it may have small dents in the body. If so, you may have decided to try to fix the damage yourself. The three steps below will guide you through filling in the dent and covering it so it will be less noticeable, using supplies found in any hardware store, automotive store, or home improvement center.

Step 1:  Fill The Underside With Spray Foam Insulation

Because fiberglass is relatively thin, you will first need to strengthen the underside of the dent before repairing it to give it a sturdy base. This can be done with a can of spray foam insulation. 

While inspecting the dent, look for a hole that will accommodate the can's applicator. If you do not see any, or if the opening is too small, use a drill with a bit that is the same size as the applicator's opening. Slowly drill the hole, being careful not to apply too much pressure or go too deep. This could damage the interior of the RV.

Once you have a hole large enough for the applicator, insert it and spray the foam into the opening until a small amount seeps out of it. Remove the applicator and let the foam set up according to the insulation's instructions.

If any foam has oozed out of the hole, use a piece of 800-grit sandpaper to smooth it until it is flush with surface of the RV's body. Then, go on to the next step.

Step 2:  Attach Fiberglass Mesh Over The Dent

Once you have provided a strong base for the dent, the next step involves attaching a piece of fiberglass mesh over the dent. This will give you a workable surface on which to apply the epoxy resin in the next step.

Take a sheet of the mesh and place it on the damaged area. Using a black permanent marker, trace the size of the piece you will need. Allow an inch past the dent to ensure complete coverage.

Cut the mesh just inside of the marking to keep from having the ink show up on your RV's body. Then, apply a small amount of epoxy glue to the edges of the piece and affix it to the body. Allow a few minutes for the glue to dry, then go on to the third step.

Step 3:  Apply A Layer Of Epoxy Resin

In this step, a layer of epoxy resin is applied to the mesh. Once it dries, it creates a hard, protective surface that will prevent the damage from getting any larger. You will need a can of epoxy resin, a wooden paint stirrer, and a nylon paint brush for this step.

Open the can of epoxy resin and use the stirrer to thoroughly mix the contents. After you have mixed the epoxy resin, dip your brush halfway into the resin. Do not completely coat the brush because you will have less control when applying it.

Using horizontal strokes, apply a thin layer of the epoxy resin onto the fiberglass mesh. Once you have covered the entire piece, let it dry for about 10 to 15 minutes. Then, apply a second coat. 

After following the steps above, the dents should be less noticeable, especially if you spray paint over the patch. However, if you find that the damage is more extensive than your first suspected, you may want to take your vehicle to an auto body shop that specializes in RV collision repair. They can inspect the damage and give you options on how they can fix it.