# Rear Cap Fiberglass Repair: Cost, Hours and Process in Hacienda Heights Rear cap fiberglass repair covers the molded rear end of a motorhome, fifth wheel or travel trailer, including the ladder mount area, taillight housings, the spare tire or bumper mounting points and the roof to cap seam. Most of what we see here is backing damage or a stress crack from a bracket. ## Specifications - Price band: $750 to $12,000 plus - Shop hours: 4 to 60 plus hours - Turnaround tier: Moderate body - Insurance billable: yes - Parts lead time: Resin, cloth and hardware in stock, 20 to 60 business days for a molded OEM rear cap where one is still tooled, longer or unavailable on discontinued models - OEM brands: Lippert, Crane Composites, Filon, Lamilux, West System, Alpha Systems ## Rear cap damage starts with backing and ends with the ladder The damage patterns on a rear cap are narrower and more predictable than on a front cap, and knowing them shortens the diagnosis. The first is backing damage, low on the cap at one corner, from a post, a wall, a dumpster or another vehicle. It arrives crushed rather than cracked, because a molded cap absorbs a slow impact by deforming, and deformed laminate has broken fiber whether or not it split open. The second is bracket stress. A rear cap is where owners hang things: a ladder, a spare tire carrier, a bike rack, a receiver, a cargo box. Each of those is a point load applied to a thin molded panel, and unless there is a proper backing plate spreading it, the laminate cracks out from the fastener. That crack has nothing to do with an impact and everything to do with load, which means it comes straight back if the bracket goes on the same way afterward. The third is the seam. The roof to cap joint is the highest sealant joint on the coach and it takes the most flex, so it opens, and it drains into the rear wall. That is why so many rear cap jobs turn out to include substrate work in the rear wall, and why we read moisture below the seam before writing anything. ## Stress cracks that radiate from a bracket rather than an impact This is the pattern most often misrepaired, so it is worth explaining what a correct fix looks like. A crack running out from a ladder or carrier fastener means the laminate at that point is being asked to carry more load than its thickness supports. Grinding, laying up and refinishing the crack restores the surface and does nothing about the cause. The correct repair rebuilds the laminate and then changes how the load enters it. That means a backing plate or a laid up thickened pad on the reverse side, spreading the fastener load across a much larger area, and it means checking whether the bracket is bolted to cap laminate at all or is supposed to land on framing behind it. On a lot of coaches the ladder is designed to fasten into a stud or a factory backer, and the crack exists because a previous installer missed it by two inches. The same logic applies to a spare tire carrier, which is the worst offender because it is heavy, it is cantilevered, and it cycles with every bump in the road. Where a carrier has begun to pull through, we will usually recommend relocating the mounting into framing rather than rebuilding the same laminate to carry the same load again. ## What sits behind a rear cap, and why the interior comes apart Access on a rear cap is generally better than on a front cap, which is one reason the hours often come out lower for comparable damage. The rear of a coach is commonly a wardrobe, a closet, a bunk area or a rear bath, and those are removable. Behind the cap there is taillight and clearance light wiring, a camera lead on many coaches, sometimes a rear vent duct, and the rear wall framing that the cap flange bonds to. Getting to the reverse side matters for the same reason it matters anywhere on fiberglass: a repair backed from behind carries load and a repair made only from outside does not. Where the interior can come out in a few hours, it comes out, because the alternative is a repair we do not believe in. The rear wall framing is the other thing we inspect while it is open. Water from the roof to cap seam travels down inside that wall, and the framing at the bottom rear corners is a common place to find corroded aluminum tube or soft wood. Finding it with the interior out is straightforward. Finding it after the cap has been refinished is expensive. - Taillight, clearance light and license plate wiring in the cap void - Backup camera lead on most coaches built in the last two decades - Rear wall framing and the cap to sidewall bond flange - Ladder and carrier backing plates, where the factory fitted them - Roof to cap transition seam and its sealant joint - Rear wardrobe, closet or bath wall panel that has to come out for access ## Molded rear cap availability and the fabrication fallback The supply picture on a rear cap is the same as on a front cap and it drives the repair decision just as hard. Where the manufacturer still runs the tooling, a molded rear cap is 20 to 60 business days out, ships crated, and arrives in gel coat white needing full refinish plus all graphics. Lippert tooling covers a large share of what is still available in this market. Where the tooling is retired, and on any coach from a builder that has closed, there is no rear cap to buy. That is when fabrication becomes the answer: a pattern taken off the existing cap or off the sound side of it, a plug and mold built here, and a new part laid up in polyester with a gel coat surface. It is slower and it is not inexpensive, and on a coach worth keeping it is the difference between a repair and a total. In between sits sectional fabrication, which is often the smart answer on a rear cap specifically. Because rear cap damage is usually concentrated at a lower corner, a molded corner section can be fabricated and scarfed into the existing cap rather than replacing the whole part. That keeps the original geometry across the rest of the cap and cuts both cost and lead time substantially. ## The wraparound refinish problem on a rear cap A rear cap wraps around two corners onto the sidewalls, and that geometry is what makes the refinish awkward. There is no natural break to end a blend at, so a repair on a rear corner has to be blended around the radius and out onto the sidewall, and the sidewall has faded at a different rate because it faces a different direction. On a white coach that is manageable. On a metallic or a three stage, it is the largest line in the job. Rear caps also carry a disproportionate share of a coach's graphics, often sweeping across the corner exactly where backing damage lands. Replacing graphics across a repair is a separate line item and on a discontinued coach the original decal set may no longer be printed, in which case the graphics get reproduced from photographs and measurements. On cost: labor at $210 per hour across four to sixty plus hours, paint supplies at $55 per paint hour, and body supplies at $5 per body hour. The band is open ended because a lower corner rebuild with a fabricated section and a wraparound metallic blend is a different animal from a ladder mount crack on a white travel trailer, even though both are rear cap fiberglass. ## Not included - Full rear cap replacement after structural damage is scoped at /rv-collision-repair/front-and-rear-cap-replacement rather than here. - Hitch, receiver and towing structure repair is chassis work and is quoted separately. - We do not perform rear cap layup at a customer location. Overhead and vertical resin work needs a controlled bay. ## Questions **I backed into a post and crushed the lower rear corner. Is that repairable?** Usually yes, and this is the most common rear cap job in the building. Crushed laminate has broken fiber whether or not it split, so the affected area gets cut out rather than pushed back, then rebuilt with backing laminate from inside. Where the corner geometry is too far gone to fair back to the original radius, we fabricate a corner section and scarf it in rather than replacing the whole cap. **Why is my RV cracking around the ladder mount when nothing hit it?** Because that is a load problem, not an impact one. The laminate at a fastener is thin and a ladder puts a concentrated cyclic load into it. Very often the ladder was fastened into cap laminate when it was designed to land on framing or a factory backer. Rebuilding the crack without fixing how the load enters the panel reproduces it, so the repair includes a backing pad or relocating the mount. **What does rear cap fiberglass repair cost?** The band on this page is open ended. A bracket stress crack with a laid up backing pad and a spot blend sits low, four to twelve hours. A crushed lower corner with a fabricated section, rear wall framing repair and a wraparound metallic blend sits at the top. Labor is $210 per hour, paint supplies add $55 per paint hour, and the teardown estimate turns the band into a number. **Is my rear cap available new if repair does not make sense?** It depends on whether the tooling is still in service. Where it is, 20 to 60 business days, crated freight, gel coat white and needing full refinish plus graphics. Where the builder has closed or the model is retired, there is no cap to buy at any lead time, and sectional fabrication into the existing cap becomes both the faster and the cheaper answer. **Should I expect water damage in the rear wall too?** Often, and we read for it on every rear cap job. The roof to cap seam is the highest sealant joint on the coach and takes the most flex, so when it opens the water runs down inside the rear wall and collects at the bottom corners. Finding corroded framing or soft luan with the interior already out is straightforward. Finding it after the cap is refinished is not. **How long will the coach be here for rear cap work?** One to three weeks for most repairs. A bracket crack with a spot blend can be under a week. A crushed corner with a fabricated section runs the longer end, and if the rear wall needs substrate work the drying stage adds days on its own. Where graphics have to be reproduced rather than ordered, add another week to that. --- Source: https://ocrv.club/rv-fiberglass-repair/rear-cap-fiberglass-repair OCRV Center, 23281 La Palma Ave, Yorba Linda, CA 92887 Phone (949) 799-3387. Email info@ocrvcenter.com. Serving Hacienda Heights and the surrounding area. 18.4 miles, 24 to 38 minutes via SR-60 west to Fullerton Rd, then south to La Palma Ave. In shop work only. All estimates are priced and credited against an authorized repair.