RV Roof Repair and Replacement in Brea, CA
RV roof repair in Brea, CA covers the membrane system and everything that penetrates it: the rubber, thermoplastic, or fiberglass surface, the seams and termination bars that hold it at the edges, the decking underneath, and every vent, skylight, antenna, and equipment flange sealed into it. Most roof problems are not the membrane itself. They are a sealant path that opened at a penetration or a termination, and water found it. Identifying which of those you have decides whether the job is a reseal measured in hours or a tear-off measured in days, and that identification is the first thing we do.
This page is about the roof as a system. It covers how membranes are built, how they fail with age and exposure, and what a full replacement actually involves. Damage caused by a specific storm event is a different question, estimated by a different method, and it is covered on our hail damage page rather than here.
- California BAR licensed ARD00288521
- 35,000 square feet facility
- All work performed in shop at our Yorba Linda facility
- Direct billing with 16 carriers on covered claims
Ready to get this looked at?
We inspect on the lift, document the damage, and give you a written scope. The estimate fee is credited against the repair when you authorize the work.
What this repair covers
Roof work runs from resealing a single vent flange to stripping a coach to bare framing and rebuilding the entire deck and membrane. In between are the jobs that make up most of the volume: replacing a section of failed membrane, rebedding every penetration on a roof whose sealant has reached the end of its service life, and replacing decking under a localized leak before it spreads.
It also covers the components that live in the roof. Vent lids and garnishes, skylight domes, air conditioner gaskets, antenna bases, and ladder mounts are all penetrations, and every one of them is a potential water path. A roof job that replaces membrane and reuses tired flange hardware has fixed half the problem.
In scope on this page:
- Membrane inspection, seam evaluation, and moisture mapping of the decking
- Sealant removal and rebedding at every roof penetration
- Termination bar replacement and re-sealing at the drip rail and cap joints
- Section repair and patching of EPDM and TPO membranes
- Full tear-off, decking replacement, and new membrane installation
- Fiberglass roof crack repair and refinish at equipment openings
- Vent lid, garnish, skylight dome, and roof hardware replacement
- Air conditioner removal, gasket replacement, and reinstallation to correct compression
| System | Typical thickness | Seams and repair | How it ages | Service notes |
|---|---|---|---|---|
| EPDM rubber | Around 45 to 60 thousandths of an inch | Seamed with tape and lap sealant, patches bond with EPDM-specific adhesive | Chalks by design. The top layer sacrifices itself and washes off as a white residue that streaks the sidewalls | Cannot be coated with just anything. Petroleum based products attack it. Inspect sealant at least twice a year |
| TPO thermoplastic | Around 45 to 60 thousandths of an inch over a reinforcing scrim | Can be heat welded seam to seam, which makes a genuinely continuous surface | Does not chalk, so no sidewall streaking. Fails instead by scrim exposure where the top ply wears through | More puncture resistant than EPDM. A welded repair needs the right tool and the right temperature, not a patch kit |
| Fiberglass | Molded laminate, thickness varies by builder | Repaired as a composite laminate, not as a membrane, with grinding and layup | Gelcoat oxidizes and can craze. Structural cracking appears at equipment opening corners | Walkable and durable, heavier, and the most expensive to repair when it does crack |
| Aluminum sheet | Thin coil sheet over bows | Seamed and sealed mechanically, repaired by panel section | Dents and oil cans, seams work loose with flex | Found on older and on some commercial bodies. Sealant maintenance at seams is constant |
Damage and failure modes we see
A roof is a horizontal surface with a dozen holes cut in it, sitting on a structure that flexes every mile. Nearly every failure traces back to one of those two facts.
Sealant failure at penetrations
Cause: self-leveling lap sealant is a consumable. Products like Dicor 501LSW have a service life measured in a few years in direct sun, and they shrink and crack as plasticizer leaves. Every vent, antenna, and equipment flange depends on that bead plus the butyl tape under the flange.
Symptom: visible cracking, crazing, or separation in the sealant bead, often pulled away from either the flange edge or the membrane. Interior evidence is a stain on the ceiling panel near a penetration, which is almost never directly under the actual leak.
Delay consequence: this is the number one water entry on any RV. Water follows the roof structure to a low point before it appears inside, so by the time a stain shows, the decking along that path is already wet. Sealant is cheap. The decking it protects is not.
Termination bar and drip rail separation
Cause: the membrane is mechanically clamped at the roof edge under a termination bar or trim rail, bedded in sealant. Road vibration works the fasteners, and thermal movement between the membrane and the aluminum trim shears the sealant.
Symptom: sealant separation along the bar, fasteners standing proud, and in advanced cases the membrane edge visible or lifting at speed. Corners are always first because they carry two directions of movement.
Delay consequence: an edge failure lets water directly behind the sidewall skin rather than into the interior, which is why owners miss it entirely. It is a leading cause of sidewall delamination and it can run for years before anything shows inside.
Membrane thinning and chalk-through on EPDM
Cause: EPDM is designed with a sacrificial top layer that oxidizes and washes away, taking surface dirt with it. It is a working feature, and it means the membrane gets thinner every year by design.
Symptom: heavy white chalk residue on the roof and matching black or grey streaks down the sidewalls after rain. Late stage, the membrane becomes thin enough to tear from a fingernail and the fabric backing shows through at high traffic points.
Delay consequence: once a membrane is thin enough to tear, patching it is a temporary measure at best, because the patch bonds to material that is itself failing. That is the point at which the honest recommendation is replacement rather than another season of repairs.
Scrim exposure and weld failure on TPO
Cause: abrasion, foot traffic on a small area, or a manufacturing weld that never fully fused. TPO is built over a reinforcing scrim, and once the top ply is worn through, the scrim is exposed and wicks water along its fibers.
Symptom: a matte, slightly fibrous looking area where the surface sheen changed, often in a walk path between the ladder and the air conditioner. Failed factory welds show as a fine line lifting at a seam.
Delay consequence: the scrim carries water sideways, so a small exposure spreads wetness across an area much larger than the visible defect. TPO repairs are heat welded, and a welded repair to sound material holds. A weld to a wet, wicking scrim does not.
Decking rot under a long running leak
Cause: any of the above, left long enough. The plywood or luan decking absorbs water, loses strength, and eventually delaminates internally.
Symptom: a soft, springy area underfoot on the roof, a visible sag between roof bows, and often a musty smell inside before any stain appears. Probing a suspect area confirms it quickly.
Delay consequence: rotted decking will not hold a fastener, which means every roof-mounted component in that area has lost its anchorage. It also spreads along the grain and along the framing, so the replacement area grows with time. Where water has reached the walls or floor, the job also involves subfloor scope, which is handled separately.
Cracking at fiberglass roof openings
Cause: stress concentration at the square corners of an air conditioner or vent opening cut into a molded fiberglass roof, combined with the cyclic load of a heavy unit bouncing on it.
Symptom: cracks running diagonally from the corners of the opening, sometimes with gelcoat crazing around the mounting flange, and a unit that has begun to move perceptibly when the roof is walked.
Delay consequence: those cracks propagate into the laminate and eventually reach the reinforcement, at which point the roof is losing structural continuity around a hole with a heavy appliance in it. Repairing early means a laminate patch. Repairing late means rebuilding the opening.
How we perform this repair
Roof work starts with finding out how far the water went, because the visible failure and the wet area are almost never the same size.
The sequence, start to finish:
- Inspect and map the roof. Every penetration, seam, and termination is examined, and the decking is probed and tapped across the whole surface. Soft areas are mapped and marked. Where an active leak is suspected but not obvious, a controlled water test isolates the entry point from the top down.
- Decide reseal against section against tear-off. A sound membrane with failed sealant is a reseal. Localized damage with sound decking is a section repair. A thin or torn membrane, or soft decking across a meaningful area, is a tear-off, and we say which before any work is authorized.
- Remove roof-mounted components. Air conditioners, vents, skylights, antennas, and ladder mounts come off. Every one is inspected, and gaskets are replaced rather than reused, since a compressed twelve year old air conditioner gasket will not seal again at the same torque.
- Strip the old membrane and inspect the deck. On a tear-off the membrane and its adhesive are removed back to the decking, and the decking is inspected bare. Compromised plywood or luan is cut out at the roof bows and replaced in kind, with backing where a joint does not land on a bow.
- Bond the new membrane. The deck is cleaned and the membrane adhesive is rolled on to the coverage rate the manufacturer specifies, using a product matched to the membrane, such as an Alpha Systems or Dicor water-based adhesive for EPDM. The membrane is rolled out from the centerline, worked outward to eliminate air, and allowed to tack before trimming.
- Terminate the edges. The membrane is wrapped and clamped at the drip rail or under a termination bar with fresh fasteners and bedding sealant, then the trim is reinstalled. Corners are the highest-risk point and get built up deliberately rather than being trimmed tight.
- Reset penetrations and seal. Every flange is bedded on fresh butyl tape, typically a Dicor butyl in a thickness matched to the flange, fastened to correct compression, and then sealed. Self-leveling lap sealant such as Dicor 501LSW goes on horizontal surfaces, and a non-sag product goes on any vertical or near vertical surface where self-leveling would run. Cure time is respected before the vehicle is released.
What this costs and how we quote it
Roof work is quoted by square footage of membrane, by the number of penetrations that have to be removed and rebedded, and by decking replacement area. Those three lines behave independently: a small roof with eight penetrations can carry more labor than a larger roof with three, because every penetration means removal, cleanup, new bedding, refastening, and sealing.
The line that changes after work starts is decking, since the true extent of soft plywood is only visible once the membrane is off. We map and quote what the probe finds, and we photograph and document any additional area discovered during the strip rather than absorbing it silently. Material choice also moves the number, since membrane, adhesive, butyl, and sealant are consumed by area and by penetration count. Rates and the paid inspection are on the pricing page.
Vehicles we perform this on
Membrane type and roof geometry vary enormously across platforms, and both drive the method.
- Class A gas motorhomes, which carry the largest single membrane area we install
- Travel trailers, the platform where EPDM chalk-through and edge termination failure appear earliest
- Fifth wheels, where the step down between the front and rear roof sections adds terminations and therefore risk
- Toy haulers, where a large flat roof with multiple units means a high penetration count
- Transit buses and school buses, where roof hatches and equipment flanges are the failure points rather than the membrane
What this page does not cover
- hail damage repair Storm impact causation and dent counting are owned there, not on this page.
- water damage and subfloor Rotted floors, walls, and framing below the roof deck are a separate repair.
- RV HVAC repair The air conditioner itself is serviced there. We only remove and reseal it here.
- awning repair Awning rails mount to the sidewall, not the roof membrane.
Get a written scope before the damage spreads
We inspect on the lift, document the damage, and give you a written scope. The estimate fee is credited against the repair when you authorize the work.
If this damage is on an insurance claim
Roof claims turn on cause. A membrane that wore out, sealant that reached the end of its service life, and decking that rotted from a slow leak are all gradual causes and are excluded from nearly every policy, no matter how expensive the resulting repair is. A roof that was punctured by a specific identifiable event, such as a branch or a low clearance strike, is a covered loss with a date behind it. The difficult cases are the ones in between, where a covered event opened a path and gradual water damage followed, and those are decided on how well the sequence is documented at inspection. Our page on water and storm claims explains how carriers separate the covered event from the deterioration that followed it.
Why Brea owners bring this work to us
A roof replacement is a week-scale job that cannot be exposed to weather midway through, and a reseal still needs cure time before the vehicle sees water. Both argue for doing it indoors at a shop rather than in a driveway, and from Brea the trip east takes about fifteen minutes each way.
Two things matter here specifically. First, roof work happens under cover on rolling platforms rather than on a ladder in a lot, which means the membrane is never partially open with weather coming and the technician can actually kneel where the work is. Second, every penetration on the roof gets removed and rebedded on a tear-off rather than being sealed around, because a new membrane sealed to a twelve year old air conditioner gasket is a new roof with the old leak still in it. We handle adhesives and solvents under EPA identification CAL000367879, which matters for what can legally be used on a job this size.
Frequently asked questions
How do I know whether my RV roof needs a reseal or a full replacement?
The membrane decides. If the membrane is still thick and intact and the failures are cracked sealant at penetrations and terminations, a reseal is the correct repair and it is a fraction of the cost. If the membrane tears under a fingernail, shows fabric backing, or the decking is soft across a meaningful area, resealing buys a season at most. We probe the decking, inspect the membrane thickness and condition, and give you the honest classification before quoting.
What is the difference between EPDM and TPO RV roofs?
EPDM is a synthetic rubber with a sacrificial top layer that chalks by design, which is why EPDM coaches get white residue on the roof and dark streaks down the sidewalls. TPO is a thermoplastic over a reinforcing scrim that does not chalk and can be heat welded, which produces genuinely continuous seams and better puncture resistance. EPDM repairs use adhesives and tapes. TPO repairs use heat welding. Neither is universally better, but they are not interchangeable in repair method or in the products used on them.
How often does RV roof sealant need to be replaced?
Inspect at least twice a year and expect to rebed penetrations somewhere in the range of every four to six years in this climate, sooner on a coach stored uncovered. Self-leveling lap sealant is a consumable that shrinks and cracks as its plasticizer leaves, and direct California sun accelerates that. Adding a fresh bead over cracked old sealant is a short term measure at best, since the new product bonds to failing material. Proper rebedding means removing the old sealant down to the flange.
Can you patch an RV roof membrane or does the whole thing come off?
Patching works when the surrounding membrane is sound and the decking under the patch is dry. On EPDM the patch is bonded with an EPDM-specific adhesive and sealed at the perimeter. On TPO it is heat welded, which produces a repair as strong as the original sheet. What patching cannot fix is a membrane that has thinned throughout, because the patch is only as good as what it bonds to, and it cannot fix wet decking, which has to be opened up regardless.
What causes black streaks down the sides of an RV?
Chalking from an EPDM rubber roof. The membrane's top layer is sacrificial and oxidizes into a fine residue, which is what keeps the roof surface releasing dirt. Rain carries that residue over the edge and down the sidewalls, where it deposits as streaks. It is normal for the roof and cosmetic for the walls. A sealed or coated sidewall resists it far better than an oxidized one, which is why the streaks stain badly on a chalky gelcoat and rinse off a corrected surface.
Does a roof leak always show up as a stain inside?
No, and assuming it does is how roofs get replaced instead of resealed. Water entering at a termination bar or a drip rail commonly runs down inside the sidewall cavity, never touching the ceiling panel, and the first symptom is a delaminated or soft sidewall rather than a stain. Water entering at a penetration follows the roof framing to a low point before it drops, so an interior stain rarely sits under the actual entry. Both are reasons the inspection covers the whole roof rather than the area near the stain.
Do air conditioners have to come off during a roof replacement?
Yes, and the gasket underneath gets replaced rather than reused. A rooftop air conditioner seals to the roof opening with a thick foam gasket that is compressed by the mounting bolts, and after years of heat and compression that gasket has taken a permanent set. Reinstalling on the old gasket at the correct torque will not restore the seal. Every penetration on a tear-off comes off, gets new bedding, and goes back to specified compression, which is much of why a tear-off is a multi-day job.
Can a fiberglass RV roof be repaired or does it need replacing?
It is repaired as a composite laminate rather than replaced as a membrane. Cracks are ground back to a tapered scarf, rebuilt with mat and cloth in resin, faired, and refinished. The common location is the corner of an air conditioner or vent opening, where a square corner concentrates stress and a heavy unit cycles it. Repairing while the crack is confined to the gelcoat and outer plies is straightforward. Once it runs into the reinforcement, the opening area itself has to be rebuilt.
Written and reviewed by the OCRV Center Technical Team. Last updated .
Book your paid estimate
We inspect on the lift, document the damage, and give you a written scope. The estimate fee is credited against the repair when you authorize the work.
Related repairs and pages
- water damage and subfloor repairWhere a roof leak that reached the walls or floor gets addressed.
- sidewall delamination from an edge leakThe usual downstream consequence of a failed termination bar.
- rooftop air conditioner serviceCoordinated whenever a unit comes off for roof work.
- fiberglass roof crack repairMolded roofs are laminate repairs, not membrane repairs.
- skylight and roof glass replacementDomes and skylights are penetrations like any other.
- solar panel mounting on a roofBest done at the same time as a membrane replacement.
- removing chalk streaks from sidewallsThe cosmetic half of an EPDM chalking problem.
- water and storm claimsHow carriers separate a covered event from gradual deterioration.
- Class A gas motorhome repair
- travel trailer repair
- toy hauler repair
- transit bus body repair
- how membrane area and penetration count are billed
- how a multi-day job runs at our shop