# RV Window and Glass Replacement for San Clemente Owners

> RV window and glass service covers frame reseal and replacement on Hehr, A&E and Kinro units, one-piece and two-piece Class A windshields, fogged dual pane glass, skylights, mirrors and custom fabricated glass. All work is done in our 35,000 square foot Yorba Linda shop.

**Type:** Repair service  
**Canonical:** https://ocrv.pro/repairs/window-and-glass  
**Updated:** 2026-07-29

## Summary

RV windows leak at the frame flange, not the glass. We reseal and replace Hehr, A&E and Kinro units, plus Class A windshields. Range $250 to $7,500.

The call almost always starts the same way. There is water on the sill under a window, or a dark line running down the wallboard beside it, and the owner has already run a bead of clear silicone around the outside of the glass twice. It did not stop. It never does, because the water is not coming in where they think it is.

RV windows are not car windows. A car windshield is bonded directly into the body opening with urethane and the glass itself is the seal. An RV side window is a complete assembly: a glass pane held in a frame, and that frame is clamped through the sidewall with butyl tape between the flange and the skin. The glass is almost never the leak. The butyl behind the flange is, and no amount of silicone on the outside reaches it.

That distinction changes everything about the repair. Fixing the leak means pulling the window, scraping the old butyl, cleaning both surfaces, checking whether the wall under the flange has softened, and reinstalling with fresh tape and correct fastener torque. It is a two to four hour job on most units and it actually works, which is more than can be said for the tenth tube of sealant.

## RV Windows Leak at the Frame, Not at the Glass

Every clamp-ring RV window works the same way. An outer frame with a flange sits against the exterior skin over a continuous bead of butyl tape. An inner ring pulls through from inside with screws, sandwiching the sidewall between them. The butyl is the entire waterproofing system. It has no adhesive strength worth mentioning, it works purely by staying compressed and staying pliable.

Butyl fails two ways in this climate. It hardens under years of UV and heat cycling until it no longer flows into the gap, and it takes a compression set so it does not rebound when the wall moves. Once either happens, a path opens between the flange and the skin. Water enters at the top flange, runs down inside the wall cavity behind the frame, and appears at the sill or below it, which is why owners chase the bottom of the window when the failure is at the top.

The other failure point is fastener torque. Overtightened screws crush the butyl completely out of the joint and dimple the skin, leaving nothing sealing the middle span between fasteners. Undertightened screws never compress it at all. Both are common on windows that have been out before. We set fasteners to a consistent snug pattern and we do not reuse hardened butyl, ever.

- **Butyl tape is the seal:** Not the glass, not the exterior caulk line. A continuous compressed butyl bead between the frame flange and the skin is the only thing keeping water out of that wall.
- **Compression set and hardening:** UV and heat cycling harden butyl until it stops flowing into the gap and stops rebounding when the wall flexes. Ten to fifteen years is a normal service life here.
- **Water enters high, appears low:** The path opens at the top flange, runs down behind the frame inside the cavity, and shows at the sill. Chasing the sill with sealant treats the symptom, never the source.
- **Fastener torque pattern:** Overtightening squeezes butyl out of the joint and dimples the skin. Undertightening never compresses it. Both leave unsealed span between fasteners.
- **Check the wall before reinstall:** With the window out we meter the opening for moisture. A soft or wet flange area means substrate repair comes first, because new butyl on rotten luan seals nothing.

## Identifying the Window You Actually Have: Hehr, A&E and Kinro

Three suppliers cover the overwhelming majority of RV side and rear glass. Hehr International is the long-standing name in motorhome and higher-end towable windows, with a large catalog of frame profiles and both single and dual pane. A&E, the older Dometic lineage, is on a great many coaches from the eighties through the two thousands. Kinro, now under Lippert, dominates the mass-market travel trailer and fifth wheel space.

None of them are cross-compatible. Frame depth is matched to sidewall thickness, and sidewall thickness varies by manufacturer and model year. A window that is the right rough opening and the right glass size will still not seal if the frame depth is wrong for your wall, because the clamp ring will bottom out before it compresses the butyl. This is the single most common mistake we see on owner-sourced replacement windows.

On intake we record the manufacturer stamp, the frame profile, the wall thickness measured at the opening, the rough opening dimensions and whether the unit is single or dual pane. That gets us the correct part. Where a discontinued unit cannot be sourced, we fabricate replacement glass to the existing frame or adapt a current-production frame to the opening, both of which we do in house.

- **Hehr International:** Broad catalog across motorhomes and premium towables, single and dual pane. Frame profiles are model specific, so identification comes from the stamp rather than from measurement alone.
- **A&E and older Dometic:** Very common on coaches from the eighties through the two thousands. Many profiles are discontinued, which usually means fabricating glass to the existing frame instead of replacing the unit.
- **Kinro and Lippert:** The volume supplier on travel trailers and fifth wheels. Generally well supported for current production, with sliders and torque style units being the common configurations.
- **Wall thickness is the trap:** Frame depth must match your sidewall. Correct rough opening with wrong frame depth means the clamp ring bottoms out and never compresses the butyl. This kills most owner-sourced parts.
- **Custom glass fabrication:** When a frame profile is discontinued we cut and temper replacement glass to the existing frame rather than forcing a modern unit into a wall it does not fit.

## Class A Windshields Are a One-Piece or Two-Piece Decision

Motorhome windshields are a different animal entirely from side glass. They are large, curved, heavy and set into a gasket or bonded into the cap opening, and on a Class A the glass is frequently the largest single piece on the vehicle. A two-piece configuration uses a center divider bar and two curved panels. A one-piece uses a single laminated panel and no divider. Which one you have is determined by the coach, not by choice.

Two-piece is the more forgiving repair. If one side takes a rock, you replace that half. The divider bar gasket has to be renewed at the same time, because it is the primary water path on that design and it is invariably hardened by the time the glass gets hit. One-piece replacement is more expensive because the glass costs more and because handling a panel that size safely takes more people and more setup.

Either way, the failure we see after a bad windshield job is water intrusion at the lower corners, where the gasket meets the cap and where the cowl drains. Those corners have to be sealed as a deliberate step, not left to the gasket. We also inspect the cap opening flange while the glass is out, because a coach that has leaked at a windshield corner for a couple of seasons frequently has a soft area behind the dash that nobody has ever seen.

- **Two-piece with divider bar:** One side can be replaced independently, which is cheaper. The divider bar gasket is the primary water path on this design and gets renewed at the same time as a rule.
- **One-piece laminated:** A single large curved panel. Higher glass cost and more setup and handling labor, but no center water path and a cleaner sight line when done correctly.
- **Lower corner sealing:** The bottom corners where the gasket meets the cap and the cowl drain are the most common post-install leak. They get sealed as a deliberate step, not left to gasket compression.
- **Inspect the opening flange:** With the glass out we check the cap flange and the structure behind the dash for softening. Years of corner leakage frequently hide real substrate damage there.

## Why Dual Pane Windows Fog and What Can Actually Be Done

A dual pane RV window is two panes with a sealed air or gas gap between them and a perimeter seal holding it. When that perimeter seal fails, ambient air carrying moisture enters the gap. On the coast, that ambient air is the marine layer. The moisture condenses on the inner surfaces during a temperature swing, and once it is inside the sealed cavity there is no way for it to leave.

The result is the permanent haze people describe as fogging, and over time it deposits mineral residue on the inner glass surfaces that will not clean off even if you could reach it. Seal failure is accelerated by altitude changes, which is why coaches that run the Sierra or head to Big Bear see it earlier, and by the daily thermal cycle of a marine morning and a hot afternoon. Coaches stored near the water in Capistrano Beach or Shorecliffs tend to show it sooner than coaches kept inland.

The honest answer on repair is that the sealed unit is a sealed unit. Drilling and drying it is a temporary cosmetic measure that restores clarity for a season and then reintroduces the same moisture, plus it leaves permanent holes in the glass. The real fix is a new sealed insulated glass unit installed into your existing frame, which is what we do. On discontinued frames we fabricate the unit to the frame dimensions. Single pane conversion is possible and cheaper, but you lose the thermal and acoustic benefit, and in coastal humidity you will get more interior condensation on the glass.

- **Perimeter seal failure:** The edge seal holding the sealed gap loses integrity and admits humid ambient air. Once moisture is inside the cavity there is no drying path that lasts.
- **Altitude and thermal cycling:** Pressure changes from mountain runs and the daily marine morning to hot afternoon swing both pump the seal. Coaches that travel elevation see fogging earlier.
- **Drilling is not a repair:** Drill and dry restores clarity briefly and reintroduces the same moisture within a season or two, plus it leaves permanent holes in the unit.
- **New sealed unit in your frame:** The correct repair is a replacement insulated glass unit fitted to the existing frame, fabricated to dimension where the original is discontinued.

## Tint, UV Film, Mirrors and Skylights Round Out the Glass Work

Beyond the structural glass, there is a category of work that owners in this area ask for constantly because of sun exposure. Ceramic UV film on side and rear glass cuts heat load and protects interior upholstery and wood from fading, which matters on a coach that sits in a Rancho San Clemente driveway most of the year with a south exposure. Film goes on properly prepped glass with the window in place, and it does not go over fogged dual pane, because you would be sealing haze under it permanently.

Mirror work covers both flat and convex heads, powered and heated mirror assemblies, and the mounting arms that crack at the base from years of road vibration. Powered mirror failures are usually the switch or the harness where it flexes at the door jamb rather than the motor itself, so that is a diagnostic question rather than a parts question. A cracked mirror arm on a Class A is also a safety item, because a head that has lost rigidity vibrates enough at freeway speed that the image is unusable exactly when you need to change lanes.

Skylights are technically glass work and functionally roof work, which is why they are a common leak source that gets assigned to the wrong trade. An acrylic skylight dome goes brittle under a decade of UV and cracks at a fastener, and the flange seal fails on the same clock as everything else on the roof. Replacement runs $350 to $2,500 and includes resealing the flange, because a new dome on old sealant is a leak you paid for.

- **Ceramic UV and heat rejection film:** Cuts solar heat load and slows interior fade on a coach with sun exposure. Applied to prepped glass in place. Not applied over fogged dual pane units.
- **Mirror heads and arms:** Flat and convex heads, powered and heated assemblies, and mounting arms that crack at the base from road vibration. Powered failures are usually switch or harness.
- **Skylight domes:** Acrylic goes brittle under a decade of UV and cracks at a fastener. Replacement always includes resealing the flange, not just swapping the dome.
- **Escape and emergency windows:** Egress units have latch and hinge hardware that must operate to code. We verify release function after any reseal, because a stuck egress window is a real safety issue.

## What RV Window and Glass Work Costs

Glass work has a wide range because a single window reseal and a Class A one-piece windshield are not the same category of job. A straightforward frame reseal on an accessible side window is one to two hours. A discontinued Hehr unit that needs custom fabricated glass and substrate repair behind the flange is a different number entirely, and the substrate is usually what drives it.

Body and paint labor is posted at $210 per hour. Our RV systems estimate is $150 and is credited back against the repair if you authorize the work with us. Glass breakage from a rock strike or vandalism is normally a covered comprehensive claim with a separate and often lower glass deductible, so bring your policy information at intake and we will bill the carrier direct.

| Line item | Range | Hours |
| --- | --- | --- |
| RV windshield replacement, Class A one or two piece | $2,500 to $7,500 | 6 to 18 |
| Window and frame reseal and replacement, Hehr, A&E, Kinro | $250 to $3,500 | 1 to 14 |
| Window repair, reseal and replacement | $250 to $2,500 | 1 to 10 |
| Window install, side, rear and sliding | $400 to $3,500 | 2 to 14 |
| Skylight repair and replacement | $350 to $2,500 | 1 to 10 |
| Body and paint labor, posted hourly rate | $210 to $210 | 1 to 1 |
| RV systems estimate | $150 to $150 |  |

## Pricing

| Line item | Range | Hours |
| --- | --- | --- |
| RV windshield replacement, Class A one or two piece | $2,500 to $7,500 | 6 to 18 |
| Window and frame reseal and replacement, Hehr, A&E, Kinro | $250 to $3,500 | 1 to 14 |
| Window repair, reseal and replacement | $250 to $2,500 | 1 to 10 |
| Window install, side, rear and sliding | $400 to $3,500 | 2 to 14 |
| Skylight repair and replacement | $350 to $2,500 | 1 to 10 |
| Body and paint labor, posted hourly rate | $210 to $210 | 1 to 1 |
| RV systems estimate | $150 to $150 |  |

## Process

1. **Identify and measure** (Day 1). Manufacturer stamp, frame profile, rough opening and measured sidewall thickness get recorded. That combination is what makes the right part arrive.
2. **Removal and opening inspection** (Days 1 to 2). The unit comes out, old butyl gets scraped, and the opening is metered for moisture and probed for soft substrate behind the flange.
3. **Scope and parts sourcing** (Days 2 to 7). You get a written scope that separates the glass work from any substrate repair found. Parts or fabricated glass are ordered against confirmed dimensions.
4. **Substrate repair if required** (Days 3 to 10). Soft luan and framing behind the flange are replaced and allowed to cure. New butyl against wet or rotten material seals nothing, so this step is not optional.
5. **Install and seal** (Days 5 to 12). Fresh butyl, correct clamp ring engagement, consistent fastener pattern, and exterior sealant only where the design calls for it rather than as a substitute.
6. **Water test and release** (Final day). Every installed unit gets a controlled water test with an interior observer, and egress windows get their release function verified before the coach goes back.

## What is included

- Window identification from manufacturer stamp, profile and measured wall thickness
- Moisture metering of the opening with the window removed
- Complete removal of hardened butyl from both frame and skin
- Fresh butyl tape installation with a consistent fastener torque pattern
- Substrate repair behind the flange where the wall has softened
- Class A windshield replacement with divider bar gasket renewal on two-piece units
- Deliberate lower corner sealing on every windshield install
- Replacement sealed insulated glass units for fogged dual pane windows
- Custom cut and tempered glass where the original frame is discontinued
- Water test on every installed or resealed unit before release

## Questions

### Why does my RV window still leak after I sealed around it?

Because the seal is not on the outside. RV windows are clamped through the sidewall with butyl tape between the frame flange and the skin, and that butyl is the entire waterproofing system. When it hardens, water enters at the top flange and runs down inside the wall. Silicone on the exterior cannot reach that path. The fix is pulling the unit and reinstalling on fresh butyl.

### How much does an RV windshield replacement cost?

A Class A windshield, one piece or two piece, runs $2,500 to $7,500 across six to eighteen labor hours. Two-piece is cheaper when only one side is damaged, though the divider bar gasket gets renewed at the same time. One-piece costs more in glass and in handling labor. Rock strike damage is normally a covered comprehensive claim, often with a lower glass deductible.

### Can a fogged dual pane RV window be repaired without replacing the glass?

Not durably. The fog is moisture inside a failed sealed unit, and drill and dry approaches restore clarity for a season before the same humid air returns. The real repair is a new sealed insulated glass unit fitted into your existing frame, fabricated to dimension when the original is discontinued. Converting to single pane is cheaper but you lose thermal and acoustic performance.

### Does insurance cover RV glass damage?

Rock strikes, vandalism and storm damage are typically covered under comprehensive, and many carriers apply a separate glass deductible that is lower than your standard comprehensive deductible. Seal failure, fogging and butyl degradation are wear items and are not covered. We bill carriers direct, so bring your policy and claim number to intake and we will handle the adjuster.

### How long does an RV window replacement take?

A straightforward frame reseal on an accessible side window is one to two days in the shop. A replacement unit is three to seven days, mostly parts transit. Custom fabricated glass for a discontinued frame adds one to two weeks. If we find soft substrate behind the flange, add three to ten days for the wall repair and cure before the window can go back in.

### Do you do glass work on Sprinter, Transit and ProMaster conversions?

Yes. Van conversions typically mix factory bonded automotive glass with aftermarket RV style windows cut into the panels, and those aftermarket units are the ones that leak. They are usually clamp-ring windows in a thin steel wall, so the frame depth and the cut edge treatment both matter. We check the cut edge for corrosion before resealing, because bare steel there rusts fast in coastal air.

## Related

- https://ocrv.pro/repairs/water-damage-and-delamination
- https://ocrv.pro/repairs/awning-and-slide-toppers
- https://ocrv.pro/rv-collision-repair
- https://ocrv.pro/rv-body-shop
- https://ocrv.pro/rv-roof-repair
- https://ocrv.pro/what-we-fix/rvs-and-motorhomes
- https://ocrv.pro/claims/how-claims-work