Roof Repair and Replacement for West Covina Owners

Where RV roof leaks actually start

Almost no RV roof fails in the middle of the sheet. It fails at the holes and at the edges. Every roof vent, powered fan, radio antenna, solar bracket, ladder mount, air conditioner and skylight is a rectangle cut clean through the membrane and the decking underneath it. Each one gets bedded in butyl tape and capped with a bead of self leveling lap sealant. That bead is a consumable part, not a permanent one. Sun bakes it, it shrinks, it splits a hairline at the edge of the flange, and water walks in underneath where nothing is visible from above.

The second failure point is the termination. The membrane has to end somewhere: at the front cap seam, at the rear cap seam, and along the two side rails under the drip edge. Those terminations are held down by a screwed trim strip and covered in non sag sealant. When that bead shrinks, water runs down the screw shanks straight into the wall cavity. Owners usually notice a stain on an upper wall panel or a swollen cabinet stile months before anything shows up on the ceiling.

We see the same sequence over and over on units coming to us from West Covina. A trailer parked at home in Woodside Village or stored on a lot near Eastland Center sits uncovered through a full summer, cools every night, heats every afternoon, and the sealant works itself apart through pure thermal cycling. The leak is slow and seasonal. By the time it shows on the ceiling, the decking above that ceiling has usually been soft for a year.

• Air conditioner gasket and the four mounting bolts through the roof
• Roof vents and powered fans, Fan Tastic and MaxxAir housings
• Bath and galley skylight domes and their garnish flanges
• Refrigerator vent and furnace exhaust penetrations
• TV, satellite and cellular antenna bases, Winegard and King
• Solar panel brackets and the cable entry gland
• Rear ladder mounts and roof rack feet
• Front cap seam, rear cap seam and both side drip rails

EPDM, TPO, fiberglass and aluminum roofs compared

EPDM is the rubber sheet most travel trailers and fifth wheels wear. It is dark rubber with a thin white acrylic wear coat bonded on top. As that coat weathers off, the sheet chalks. The white residue running down your sidewalls after a rain is literally your roof surface leaving. The upside is that EPDM stays flexible for a long time and accepts patch material and primer well, which is why a structurally sound EPDM roof can often be stripped, resealed and recoated rather than replaced.

TPO is a thermoplastic single ply, white all the way through its thickness, with better puncture and grease resistance than EPDM. It does not chalk the same way. The tradeoff is chemistry. TPO will not accept EPDM primers and lap cements, and a patch bonded with the wrong adhesive lifts within a season. TPO also stiffens with age and tends to crack at the tight fold radius where it wraps the front cap on older units.

Fiberglass roofs are a laminated or molded panel found on diesel pushers, higher end fifth wheels and some Class C coaches. They are rigid, walkable and do not chalk, but the gelcoat crazes under sustained UV and stress cracks radiate out of any penetration that was drilled without a backing plate. A fiberglass roof does not tear the way rubber does. It splits, and the split keeps running until something stops it.

Aluminum roof sheet appears on older travel trailers, park models and vintage units. Panels lap over one another and are screwed through butyl tape. It fails by fastener back out, by galvanic corrosion where dissimilar metals touch, and by seam sealant shrinking at the lap until the joint breathes water every time the panel expands.

How we locate a roof leak before anything is cut open

Cutting a roof open to hunt for a leak is the expensive way to do it. We start inside with a pinless moisture meter and map the ceiling and upper walls on a grid, marking readings as we go. Wet material reads differently than dry material even when nothing is visibly stained, and the wet zone is always larger than the stain. That map tells us the shape of the intrusion, which usually points at one or two penetrations.

Next comes a controlled water test. We flood one zone at a time, starting low and working up, never the whole roof at once, because a single hose pass over everything tells you only that the roof leaks somewhere. One technician runs water, another watches from inside with a light and a borescope through an access point. That combination separates a vent flange leak from a cap seam leak from a window that has nothing to do with the roof at all.

The last step before an estimate is a look at the substrate. Pulling one vent or dropping the air conditioner gives us a clean edge view of the decking thickness and condition. If the luan is dark, spongy or delaminated at the cut edge, we know the repair extends past that opening. We write findings with photographs and meter readings so you can see what we saw.

Roof, slide and awning systems estimates carry a flat estimate charge, and that charge is credited back against an authorized repair. In depth diagnostic time runs at the posted diagnostic rate with a one hour minimum, also credited against an authorized repair.

Luan, azdel and rafters: what the membrane is bonded to

The membrane itself is only the raincoat. Underneath it sits a decking panel, and on the majority of trailers and fifth wheels that panel is thin luan plywood laminated to the top of the truss structure. Luan is cheap, light and utterly unforgiving about water. Once it takes moisture it swells, the plies separate, and it loses nearly all of its stiffness. It does not recover when it dries. That is why a roof that felt fine two seasons ago now sinks under a boot.

Azdel is a fiberglass reinforced polypropylene composite used as a substrate on some builds and marketed as a rot proof alternative. It genuinely does not rot. What it does not do is stop water. Moisture that gets past the membrane simply runs along the top of the azdel panel until it reaches a wood truss, a screw hole or the top plate of the sidewall, and that is where the damage shows up instead.

The trusses are typically one by two or one by three pine on stick built units, or aluminum tube on laminated coaches. Rotted wood loses fastener holding power first and structural strength second. A soft truss will not hold the screws that anchor the trim strip that holds the membrane down, so the repair chases itself in a circle until the truss is replaced. Aluminum tube trusses do not rot, but the water that soaked past them reached the wall laminate instead.

On laminated roofs the failure is delamination. Water gets between the outer skin and the foam core, the bond releases, and on the first hot afternoon the trapped moisture expands and lifts the skin into a visible bubble. Delamination is a structural repair, not a sealant repair.

Recoat, patch or full membrane replacement

A recoat is the right answer when the membrane is intact, the decking reads dry everywhere, and the actual problem is chalked surface and failed sealant. We scrape every penetration back to bare flange, remove the old butyl, re bed the components, run fresh self leveling lap sealant on the horizontal flanges and non sag sealant on the vertical terminations, then clean, prime and coat the field. Done properly this buys years, and it is by far the cheapest path.

A patch is the right answer for a localized puncture or tear with sound decking under it. A branch strike from a low limb on a residential street, a garage header, a dropped tool. We cut back to sound material, replace the affected decking section, and splice in a membrane patch with the correct primer and seam tape for that membrane chemistry. Eternabond tape is an excellent tool over a seam or a clean tear. It is a terrible substitute for a roof, and layering it over a wet substrate seals the water in rather than out.

Full replacement is the answer when the decking reads wet across a wide zone, when there are multiple soft spots, when a cap seam has separated along its length, or when the membrane itself has gone brittle and cracks wherever you press it. That job means stripping the air conditioner, every vent, the antenna, the racks and all the trim, peeling the old sheet, replacing decking and any rotted truss, then laying a fresh membrane in adhesive and re bedding every component that comes back on.

• Two or more soft areas underfoot pushes a job from recoat toward replacement
• Separation across the full width of the front cap seam usually means replacement
• Cracks that propagate when you flex the sheet mean the membrane is done
• Wet meter readings across more than a third of the ceiling area mean decking work
• A roof already carrying three or more layers of coating cannot take another one

Ponding at the air conditioner and other built in traps

The rooftop air conditioner sits in a fourteen by fourteen inch opening and seals against the roof with a foam gasket compressed by four long bolts that pull the unit down against the ceiling assembly. That gasket is the single most common leak on any RV that has one. Overtighten the bolts and the foam crushes flat and stops sealing. Undertighten and the gasket never compresses evenly, leaving a channel on one side. Either way it is a slow drip directly onto the ceiling frame.

Roof crown on most RVs is shallow, and the air conditioner shroud is a wall in the middle of it. Water backs up on the upstream side and sits there. In Southern California that puddle usually evaporates and leaves behind grit that grinds at the coating every time somebody walks it. In a real winter storm it stands for hours and finds the gasket.

Other built in traps repeat on nearly every unit we open. Solar brackets screwed down without butyl underneath. Aftermarket satellite domes installed with silicone instead of lap sealant, which never bonds properly to EPDM and peels in sheets. Ladder feet that flex every time somebody climbs. Roof sag between trusses that turns a flat panel into a shallow basin. None of these are dramatic. All of them are patient.

Bringing a roof job to Yorba Linda from West Covina

The shop is at 23281 La Palma Ave in Yorba Linda. It is not in West Covina, and we say that plainly rather than implying a second location. From most West Covina addresses it runs about 22 miles and 30 to 45 minutes: the 10 or the 60 west to the 57 south, then the 91 east to Imperial Highway. When the 57 backs up in the afternoon, Carbon Canyon Road over to the 71 is the shortcut locals use.

All roof work happens in shop. We do not offer mobile service, and roof work is exactly the job where that matters most. Membrane adhesive has a temperature window and an open time, sealant needs hours of undisturbed cure, and a stripped roof cannot be left exposed to weather or overnight dew. A covered, level bay with power and lighting is not a convenience for this work, it is a requirement for it to hold.

Plan on leaving the unit. A reseal and recoat generally runs a few days. A localized patch with decking work runs about the same. A full membrane replacement with truss and decking repair runs weeks, not days, and the range widens as soon as we open it and see how far the water traveled. We call before any additional work is authorized, and nothing gets done that you have not approved.

Shop hours are Monday through Friday 8:00 AM to 5:00 PM and Saturday 9:30 AM to 3:00 PM. Sunday is closed. Call (949) 799-3387 to get on the schedule, and tell us the year, make, floorplan and roof type if you know it so we can plan bay time.

Insurance claims on RV roof damage

Comprehensive coverage generally responds to a sudden event: hail, a falling limb at a campground, a garage header strike, a tree branch on a residential street. It generally does not respond to slow water intrusion caused by sealant that was never maintained, which carriers treat as wear and tear. Where the line falls depends on the policy and the adjuster, and the documentation you bring matters more than most owners expect.

We photograph the roof before anything is touched, record moisture meter readings across the affected area, and note the point of entry against the damage pattern. When we open a roof and find that the water traveled further than the initial scope covered, we write a supplement with photos rather than absorbing it quietly or surprising you at pickup. Adjusters approve supplements far more readily when the evidence is already assembled.

We have written roof claims with most of the carriers our customers use. Carrier names are listed to show claim experience. OCRV Center is an independent shop and is not affiliated with, endorsed by or acting as an agent of any insurer. If you are still deciding whether to file, bring the unit in and let us document the damage first so you know what you are dealing with before the claim number exists.