Collision and Structural
RV Fiberglass Repair and Delamination Correction Serving Long Beach
About 10 min left
Delamination is the separation of an RV fiberglass skin from the substrate behind it, caused almost entirely by water reaching the adhesive bond. OCRV Center repairs it by removing the affected skin, replacing wet or rotted substrate, re bonding under vacuum or mechanical pressure, and refinishing. Work runs $800 for a small localized bubble to $20,000 or more for a full sidewall.
Run your hand along the sidewall of a coach that has been sitting in Southern California sun for a decade. Where it goes soft, or ripples, or gives slightly under pressure, the fiberglass has stopped being bonded to what is behind it. That is delamination, and it is the single most common structural complaint we see on recreational vehicles.
It is also the one owners most often try to fix from the outside, with sealant, and it never works. The bond has already failed underneath. Adding a bead of caulk to the seam above it stops new water but does nothing about the water already inside or the adhesive it destroyed.
What Causes Delamination on Motorhomes and Fifth Wheels
An RV sidewall is a sandwich. Gelcoated fiberglass on the outside, a bonding adhesive, a substrate of luan plywood or foam, framing, and interior paneling. It gets its stiffness from the layers acting as one piece. Water reaching the adhesive layer breaks that relationship.
Water gets in through failed window seals, failed roof to sidewall transitions, unsealed screw penetrations from awning brackets and accessories, and marker light gaskets that went hard and cracked. On the Southern California coast, the daily thermal cycle between a marine layer morning and a hot afternoon works those seals loose faster than most owners expect.
Early Detection Before It Spreads
Press the sidewall with a flat palm across a grid pattern. Solid areas resist. Delaminated areas flex or make a faint crunching sound as the failed adhesive crumbles. Tap testing works too: bonded panel rings, unbonded panel thuds.
Catching it at one square foot is a $800 to $2,000 repair. Catching it at half a sidewall is $12,000 or more, because by then the substrate is rotted and the framing behind it may be as well.
Why Injection Kits Usually Fail
Injection kits pump adhesive through drilled holes into the void. They can work on a small, dry, recently separated area. They fail on anything else, and the reason is simple: you cannot bond to wet, rotted luan. The adhesive grabs the fiberglass on one side and mush on the other.
We inspect moisture content before recommending any approach. If the substrate reads wet, injection is not on the table and we will say so rather than sell you a repair we expect to fail.
Crack, Hole and Impact Repair
Impact damage to fiberglass behaves differently than damage to sheet metal. It does not dent, it fractures, and the fracture propagates outward as a star pattern under the gelcoat that is often much larger than the visible chip.
Proper repair means grinding back to sound laminate well past the crack termination, building the structure back with layered glass and resin at a bevel that restores full thickness, then filling, blocking and refinishing. Filling a crack without addressing the laminate underneath produces a repair that reappears within a season as the substrate continues to flex.
Full Panel Replacement and Sidewall Rebuild
When delamination has taken more than roughly a third of a sidewall, replacing the panel is usually cheaper than chasing the failure. We remove the skin, strip the wet substrate, inspect and replace any rotted framing, install new substrate, and bond a new skin under pressure.
This is a multi week project and it is not a small expense, but it produces a wall that is actually structural again. Partial repairs across a badly compromised wall tend to produce a coach that is permanently in the shop.
Refinishing and Color Match on Fiberglass
Aged gelcoat is not the color it was when it left the factory. Ultraviolet exposure has shifted it, and matching to a paint code produces a repair patch that is visibly newer than everything around it.
We match to the vehicle as it exists now, sprayed out on a test card and checked against an adjacent undamaged panel under corrected lighting, then blend into the surrounding area rather than cutting a hard edge at the repair boundary.
What Is Included
- Moisture mapping of the affected area before a repair method is selected
- Removal of separated skin and full replacement of wet or rotted substrate
- Inspection and repair of framing behind the substrate
- Re bonding under vacuum or mechanical clamping pressure
- Structural laminate rebuild on cracks and impact damage, not surface filler alone
- Color matched refinish blended into adjacent panels
- Correction of the water entry point that caused the failure in the first place
Our Process
- 1
Moisture Survey
Meter readings taken across a grid to map the true extent of wet substrate, which is almost always larger than the visible symptom.
- 2
Repair Method Selection
Localized re bond, panel section or full sidewall replacement chosen from the moisture map and substrate condition.
- 3
Skin Removal
Affected fiberglass removed cleanly to sound bonded material at the perimeter.
- 4
Substrate and Frame Repair
Wet luan or foam removed, framing inspected, rot replaced, structure returned to original thickness.
- 5
Bonding
New or original skin bonded with structural adhesive under vacuum or clamped pressure and allowed full cure.
- 6
Refinish
Faired, primed, blocked and sprayed to a color matched to the coach as it exists today, then blended.
- 7
Water Intrusion Correction
The seal, seam or penetration that let water in is repaired, otherwise the failure simply returns.
Frequently Asked Questions
How much does fiberglass repair cost on a fifth wheel?
A small localized crack or impact repair on a fifth wheel runs $800 to $2,500. A delaminated section of a few square feet with substrate replacement runs $2,500 to $6,500. A full sidewall rebuild on a large fifth wheel runs $12,000 to $20,000 or more. The single biggest cost driver is how much substrate is wet, which is why the moisture survey happens before we quote rather than after.
How do you repair delamination on an RV?
We map the wet area with a moisture meter, remove the separated fiberglass skin back to solidly bonded material, strip out the wet or rotted substrate, inspect and repair the framing behind it, install fresh substrate, and re bond the skin under vacuum or clamping pressure. Then we refinish with a color matched to the coach as it currently looks and fix the leak that caused it. Skipping the leak correction guarantees the repair fails again.
Can delamination be prevented?
Largely, yes, and it comes down to sealant maintenance. Inspect every roof to sidewall transition, window perimeter, marker light and accessory screw penetration twice a year, and reseal anything showing a crack, a gap or chalking. Most delamination we repair traces back to a single failed seal that went unnoticed for two or three seasons. Covered storage helps considerably by reducing the thermal cycling that works seals loose.
Will insurance cover delamination repair?
It depends entirely on cause. Delamination resulting from a covered event, such as a collision, a hail strike or a storm driven water intrusion, is generally covered. Delamination that developed gradually from a seal that was never maintained is typically classified as wear and neglect and denied. If your delamination followed an identifiable incident, tell us the date and what happened, because that timeline is what makes the claim viable.
Fiberglass Repair and Delamination is performed in shop at OCRV Center, 23281 La Palma Ave, Yorba Linda, CA 92887, serving Long Beach, California and the surrounding region. Call (949) 799-3387 to discuss your vehicle.
Get Your Vehicle Looked At Properly
Call the shop, describe what happened, and we will tell you what the realistic scope and timeline look like. All work is performed in shop at our 35,000 square foot facility.