--- title: "Custom Modifications in West Covina" description: "Structural and functional modifications, layout changes, equipment integration and one off builds, engineered before they are cut." canonical: https://ocrv.xyz/services/custom-fabrication/custom-modifications/ business: "OCRV Center" phone: "(949) 799-3387" address: "23281 La Palma Ave, Yorba Linda, CA 92887" market_served: "West Covina, California" --- # Custom Modifications in West Covina OCRV Center performs custom structural and functional modifications on RVs, vans, trailers and work vehicles for West Covina owners at our Yorba Linda shop. That covers window and door relocations, wall openings, layout changes, equipment integration and one off builds that no manufacturer offers as an option. **Ballpark range.** $1,000 to $25,000 and up. Ranges are planning figures, not a quote. Final numbers come from a written estimate on your vehicle. ## What counts as a custom modification here Custom modification is the category for work that changes what the vehicle is rather than restoring what it was. Deleting a window and closing the wall. Relocating an entry door. Cutting a new opening for a bay, a vent, an access panel or a slide out generator. Changing a floor plan. Building a platform, a bulkhead, a partition or a work surface into a van. Integrating equipment into a body so it looks factory instead of bolted on. It is different from repair work in that there is no original condition to return to. There is a goal, a vehicle, a structure that has rules about what it can carry, and a design that has to satisfy all three. That is why these projects start with drawings and conversations rather than with a saw. It is also different from a full interior remodel, which is its own service. Modification work is structural and functional: openings, framing, mounting, integration. When a project needs both, the modification work happens first and the finish work follows, because it is far cheaper to cut the wall before the cabinetry goes in than after. - Window deletes, relocations and new openings in sidewalls - Entry, bay and cargo door relocation or addition - Floor plan and layout changes that require framing work - Equipment integration on work vehicles, food trucks and specialty builds - Bulkheads, partitions, platforms and permanent work surfaces - Completion or correction of a conversion someone else started ## Cutting into a sidewall without weakening the vehicle An RV sidewall is a stressed assembly. The aluminum or steel framing carries load, the bonded skin adds stiffness, and the whole thing works as a panel. Cut an opening in it and you interrupt that load path. Do it without framing the opening and you get flex, then cracked skin at the corners, then a door or window that no longer seals because the opening has racked. So every opening gets framed. Verticals get added at each side of the cut and tied top and bottom into existing structure. A header spans the top. Corners get radiused rather than left square, because a square corner is a stress riser and cracks propagate from it. On larger openings we add diagonal bracing or a full perimeter frame welded up as one piece and bonded in. The other half of the job is what is inside the wall. Wiring runs, LP lines, water lines, tank vents, slide mechanisms and speaker wire all live in there, and none of them are where the manual says they are. We open a small inspection point and look before committing to a cut line. Finding a 12 volt run after the saw is through it turns a modification into a modification plus an electrical repair. ## Window deletes, door relocations and layout changes Window deletes are the most requested modification on camper conversions and expedition builds. Owners want wall space for a bed, a galley or a cabinet run, and the factory put a Hehr or Kinro unit right there. The window comes out, the opening gets framed and skinned with matching material, the seam gets bonded and sealed, and the exterior gets refinished so there is no ghost outline. Done properly, you cannot tell from ten feet away or from six inches. Door relocations are heavier work. An entry door opening carries a step, a latch, a lock, wiring for the porch light, and often the shore power inlet nearby. Moving it means framing two openings, one closed and one new, relocating everything that lived around the original, and getting the new door to seal in a plane that may not be perfectly flat. This is a multi week project on most vehicles and it is worth being honest about that up front. Layout changes range from moving a dinette to reconfiguring a bathroom wall. What determines cost is not the visible work but what runs through the walls and floor being moved: plumbing, drains that need slope, electrical, LP, and ducting. Moving a wall two feet is easy. Moving the drain line that was in it is the actual job. ## One off builds for work vehicles and specialty use A significant share of our modification work is commercial. Box trucks that need an equipment bay cut into the side. Flatbeds that need a headache rack, a crane mount and toolbox integration. Food trucks that need service window framing, equipment mounting, a fresh water and waste layout that fits the body, and exterior finish that survives daily washdown. Work vans that need partitions, roof structure and secure mounting for gear. On commercial vehicles we work on body, paint, structural and equipment install. We do not perform engine, drivetrain or DOT related inspection work on those units. That boundary is worth stating clearly because it shapes what we can take on: if the modification is about the body, the structure, the mounting or the finish, it is our work. If it is about the powertrain, it is not. Specialty builds cover the rest: workshop van and trailer interiors, expedition camper structural work, toy hauler ramp and tie down modifications, race trailer build outs, and vehicles being adapted for equipment that was never meant to go in them. These are the projects where the drawing stage matters most, because there is no reference build to copy. ## Integrating a modification with sealant, paint and existing structure The finish work on a modification is what determines whether it reads as an upgrade or as damage. A window delete with a visible patch outline, a new bay door that does not follow the body line, or a filled opening painted a shade off will be the first thing anyone notices about the vehicle. So the finish stage gets planned at the same time as the structural stage. That means matching skin material rather than using whatever sheet is on hand, because filon, fiberglass and aluminum all take filler and paint differently. It means bonding seams with a structural adhesive and mechanical fastening rather than filler alone, since filler over a butt joint will crack along the seam the first hot summer. And it means the paint department reads the color off your vehicle and blends into adjacent panels rather than taping a hard line at the repair edge. Sealant work is the other half. Every new penetration gets the correct sealant for its location: butyl under mounting flanges, self leveling lap sealant on horizontal roof seams, non sag on vertical seams, and proper primer where the substrate calls for it. We do not use one tube for everything, because the failure modes are different and they all end in the same place, which is water inside a wall you just paid to build. ## Where we say no to a modification There are projects we turn down, and it is fairer to say so on this page than at the estimate. We do not cut structural members that carry slide loads without a replacement load path, and on some coaches there is no practical replacement path. We do not move an entry door on a vehicle where the resulting opening would land in the slide swept area. We do not add weight to a chassis that is already at its rating. We also decline modifications that create a problem the owner will not see for years. Cutting a bay into a wall directly below a known roof leak. Adding a heavy roof structure to a coach with delamination in the upper sidewall. Building a permanent installation over a section of subfloor that is already soft. In each of those cases the answer is the same: fix the underlying condition first, then do the modification on a sound vehicle. When a project is technically possible but a bad idea economically, we say that too. A twenty year old coach with a failing roof and a soft floor is not the platform for a twenty thousand dollar layout change. The estimator will lay out the order of operations that gets you the most usable vehicle for the money, even when that order does not start with the project you called about. ## Frequently asked questions ### Can you remove a window and close up the wall so it does not show? Yes. This is routine work on camper conversions and expedition builds. The window and frame come out, the opening gets framed with new verticals tied into existing structure, matching skin material is bonded and mechanically fastened, seams are sealed, and the exterior is refinished with color read off your vehicle and blended into adjacent panels. Done correctly there is no visible outline in daylight and no ghosting through the paint later. ### How do I know if my idea is structurally possible on my rig? Bring the vehicle in and we will find out together. The determining factors are what framing runs through the area, what services are hiding in the wall or floor, whether the load path can be rerouted, and what the modification does to weight and balance. We open an inspection point rather than guessing from drawings, because RV construction varies a great deal even inside a single model year. ### Can you finish a van conversion someone else started and abandoned? Frequently, and it is common work. The first step is an honest assessment of what was already done, because the structural and electrical work underneath is what determines whether the project moves forward or gets partly undone. Insulation over a rusted panel, wiring run without protection, and windows installed without proper sealing all have to be corrected before finish work goes over them. We document what we find before quoting the remainder. ### How long does a major modification project take? A single window delete with refinish runs a week or so. A door relocation or a significant layout change runs several weeks with the vehicle in the building the entire time. Commercial equipment integration depends heavily on parts lead times for the equipment itself. You get a target date at authorization, and we call you if anything we uncover behind a wall moves it. ### Will a custom modification affect my insurance coverage? Talk to your carrier before the work starts. Most carriers want documented modifications listed on the policy, particularly anything that changes the value of the vehicle or its use. We provide written documentation of the work performed with photos, which is what carriers typically ask for. What we can tell you is that undocumented modifications discovered after a loss create problems at claim time, so getting it on the policy in advance is worth the phone call. --- OCRV Center, 23281 La Palma Ave, Yorba Linda, CA 92887. Phone (949) 799-3387. All work is performed in shop at the Yorba Linda facility. We do not run mobile, roadside or fleet route service. Ranges are planning figures, not a quote. Final numbers come from a written estimate on your vehicle.