Soft Floors and Bubbled Walls: Understanding RV Water Damage

Water damage is what we're known for, and it's also the work we most wish people didn't need. Almost every job we open up started as something small that somebody didn't see.

What delamination actually is

Most RV sidewalls are a sandwich: a thin fiberglass skin, glued to a layer of thin plywood, glued to foam insulation, glued to an interior panel. The whole thing holds its strength from the glue.

Water gets between those layers and the adhesive lets go. Heat and sun speed it up. The fiberglass skin, no longer bonded to anything, starts to move independently — and you see bubbles, ripples, or waves in what used to be a flat wall. Tap it and it sounds hollow.

Once the bond is broken, it does not come back. The wall has to be opened and rebuilt.

What a soft floor means

You step somewhere near the door, or by the shower, or in front of a slide, and it flexes.

RV floors are usually a laminated panel too. When the core gets wet, it swells, loses strength, and eventually rots. By the time you can feel it through the vinyl, the wood underneath has been wet a long time — and water doesn't stay in one place. It runs along the subfloor and wicks into the wall bottoms and the framing.

Where it comes from

In our experience, roughly in this order:

1. Roof penetrations. Vents, AC, skylight, antenna, the trim rail along both roof edges. Sealant fails and water runs into the roof structure, then down inside the walls.
2. Slide seals. Cracked or flattened, letting water into the slide box. Feeds the floor directly.
3. Windows. The butyl tape behind the frame dries out and shrinks.
4. The corner seams, where the sidewall meets the front and rear caps.
5. Interior plumbing — a slow drip under a sink or behind the shower doing quiet damage for a year.

Notice how many of those are sealant. That's the whole ballgame in RV construction. Everything else is downstream.

How we approach it

We start with a moisture survey. Meter readings across the walls, floor, and ceiling to map how far the wet area actually goes, plus a visual and tactile check. This matters because the visible damage is always smaller than the real damage. Nobody can quote this job from a photo.

Then we open it up. Repair means removing the affected panels and skin, taking out the wet and rotted material, replacing framing and decking, rebuilding the laminate, and — critically — fixing the water source before anything gets closed back up. Repairing the wall without finding the leak just buys you a year.

The conversation nobody likes

Sometimes we open a rig and the honest answer is that the repair costs more than the RV is worth. Extensive rot through the floor and both walls on an older unit can get there.

We'll tell you that. We'd rather lose the job than take your money for a rebuild that doesn't make financial sense. If it's borderline, we'll show you what we found and lay out the options — full repair, partial stabilization, or walking away — and let you decide.

The part you can control

Every year, before winter and again in spring: get on the roof, look at every seal, and fix what's cracked. Check your slide seals. Look at your window frames. It's a two-hour job that prevents a five-figure one.

And if you're done with the annual reseal cycle entirely, the Apex Armor spray-on roof removes the seams that cause most of this.