# Fiberglass on a Coach Is a Laminate, Not a Panel > Fiberglass repair on an RV means restoring a laminate: gelcoat over glass reinforced polyester, bonded to a substrate and a frame. The posted band is $750 to $12,000 across 4 to 60 hours. Repairing the visible damage without restoring the bond behind it is the most common reason a fiberglass repair fails twice. Source: https://ocrv.biz/services/fiberglass-repair/rv-camper-fiberglass-repair/ Business: OCRV Center, 23281 La Palma Ave, Yorba Linda, CA 92887. (949) 799-3387. Serving Tustin, California. Ballpark range: $750 to $12,000. Posted rates at https://ocrv.biz/prices/ ## What is actually in an RV fiberglass panel? Four or five layers, and every repair decision depends on which of them failed. The outer layer is gelcoat, a pigmented polyester resin about as thick as a business card. It is the finish, not the structure. Under it is the laminate: glass fibre, usually chopped strand or a light woven mat, wetted out in polyester or vinylester resin. That is the strength. Under the laminate on a sidewall is adhesive bonding it to a substrate, commonly luan plywood or a composite board. Under that is the core, either block foam or a stud grid in aluminum or wood, and finally the interior wall panel. A chip in the gelcoat is cosmetic. A star crack in the gelcoat with sound laminate behind it is cosmetic with a structural cause somewhere nearby. A crack through the laminate is structural. And a panel that is intact everywhere but sounds hollow when tapped has failed at the adhesive, which is a bond failure and is dealt with under [delamination repair](/services/fiberglass-repair/delamination-repair/). Molded caps are different again. A front or rear cap is a thicker single moulding with no substrate behind most of it, so cap damage is usually a straightforward laminate repair with a harder refinish. ## How is the true repair area determined? By tapping, not by looking. A coin, a plastic mallet or a knuckle run methodically across the panel produces a bright, sharp report over bonded laminate and a dull, hollow one where the layers have separated. The technician works outward from the damage in a grid and tapes the boundary where the sound changes. That taped outline is usually two to four times the size of the visible damage. It is also non negotiable: repairing inside it leaves a debonded ring around a solid patch, which is exactly the geometry that cracks again at the edge of the repair within a year. Moisture gets checked next. A meter on the interior surface and around window and seam penetrations shows whether water has been sitting in the substrate. Wet luan does not take adhesive and does not regain strength on drying, so any wet area gets cut out rather than dried out. Finally the cause gets identified. Impact damage is obvious. A crack radiating from the corner of a window, a door or a slide opening is a stress crack, and it is telling you that the structure around the opening is flexing. Repairing the crack without addressing the flex means repairing it again. ## What does the actual repair sequence look like? Fiberglass work is a sequence of cure cycles, and cure time is why calendar days exceed labor hours on almost every one of these jobs. - **Grind and feather.** The damaged laminate is ground back to sound material with a long, shallow taper, typically twelve to one, so the new glass overlaps a wide bonding area rather than butting an edge. - **Substrate repair.** Any wet or crushed luan and core material is cut out and replaced with matched material, bonded and clamped. - **Lamination in stages.** Glass is laid up in successive plies, each allowed to cure, building back to original thickness or slightly over. - **Fairing.** Polyester filler over the cured laminate, blocked flat with progressively finer boards. This is where the shape either comes back or does not, and it is the most skill dependent step in the job. - **Prime, block, seal.** High build primer, blocked again, then sealer so the topcoat has a uniform substrate. - **Refinish.** Colour sprayed out on a card, checked under shop light and daylight, then applied with the blend mapped across adjacent panels. At the low end of the $750 to $12,000 band sits a contained gelcoat and laminate repair on a solid colour. At the high end sits a large cap area with graphics that have to be recreated, which pulls in [custom paint and graphics](/services/paint-refinishing/custom-paint-graphics/). ## Gelcoat or paint: which finish does your coach have? It matters, because they are repaired and matched differently, and a lot of owners do not know which they have. Gelcoat is a moulded in colour. It has depth, it oxidises to a chalky surface rather than peeling, and a deep scratch shows the same colour in the bottom of it. Paint sits on top of a substrate, and a deep scratch shows a different colour underneath. On most modern coaches the sidewalls are painted over a laminate and only the caps or the roof are gelcoat, so a single vehicle can have both. Oxidised gelcoat is frequently recoverable without refinishing at all. Compounding and polishing removes the dead surface layer and brings colour back, which falls under [paint correction](/services/detailing-reconditioning/paint-correction/) at detail rates of $95 per hour rather than body rates. Where the gelcoat is too thin to cut, the panel gets refinished. Owners can check for themselves. Rub a small hidden area with polishing compound on a cloth. If colour transfers to the cloth and the spot brightens, that is oxidised gelcoat and it is recoverable. If nothing transfers, it is paint. Sibling work sits at [crack, hole and impact repair](/services/fiberglass-repair/crack-hole-impact-repair/), and all bands are posted on the [price sheet](/prices/). ## Questions ### Can gelcoat be matched exactly? Closely, and better on some colours than others. Gelcoat pigments shift with age and ultraviolet exposure, so a fresh mix to the original formula will not match a twenty year old panel. The practical approach is matching to the aged panel and blending outward, or refinishing the whole panel where a blend would show. ### Why did my previous fiberglass repair crack again at the edge? Almost always because the repair stopped at the visible damage instead of at the edge of the debonded area. A hard patch bonded inside a soft ring concentrates stress exactly at its perimeter, and that perimeter is where the new crack appears. ### Are spider cracks a problem or just cosmetic? They are cosmetic in themselves and diagnostic in what they indicate. Spider cracking in gelcoat means the laminate underneath flexed more than the gelcoat could follow. If it radiates from an opening or a mounting point, the cause is structural flex and that is what needs attention. ### Can I repair a small hole with a kit from a marine store? For a contained hole in a flat area, a competent owner can get a serviceable result. Two things go wrong most often: not tapering the edges enough, so the patch has no bonding area, and not checking for wet substrate, so the repair is bonded to material that has no strength left. ## Related - [Fiberglass Repair](https://ocrv.biz/services/fiberglass-repair/) - [Delamination Repair](https://ocrv.biz/services/fiberglass-repair/delamination-repair/) - [Crack, Hole and Impact Repair](https://ocrv.biz/services/fiberglass-repair/crack-hole-impact-repair/) - [Paint Correction](https://ocrv.biz/services/detailing-reconditioning/paint-correction/) - [Prices and Posted Rates](https://ocrv.biz/prices/)