How long before delamination becomes visible?

In our experience, about three years. It is well underway before the wall looks wavy or bubbled.

Where does the water usually get in?

Slides and their seals and caulk, window seals, and the roof — the three places water intrusion does the most damage.

Can delamination be prevented?

Much of it can, by keeping the seals and sealant that stop water in good shape. That is preventative maintenance, and it makes a big difference.

Will a pre-purchase inspection find it?

An inspection looks at the exterior and the seals where water gets in. The Premier Package adds a moisture and water intrusion evaluation.

What causes RV delamination, and how early does it start?

Delamination is the outer skin of an RV wall pulling away from the layer behind it, and it's usually driven by water getting in through a seal. It starts about three years before you can see it — so the seals, not the wall, are where to look.

What delamination is

An RV wall is built in layers. Delamination is when the outer skin separates from the layer behind it. From the outside, it eventually shows up as a wall that looks wavy, bubbled or soft in spots.

What causes it

Most of the time, water. It gets in through a seal that's failed — around a slide, a window or something on the roof — and works its way into the wall where nobody can see it.

That's why it matters that three of the five problems we find most often are seals: slide seals, roof sealant and window seals. Those are the same three places where water intrusion does the most damage.

Why you usually find out late

This is the part owners don't expect. Delamination starts about three years before it's visible. The water has been getting in, and the damage has been building, long before the wall looks any different.

So by the time you can see it from across the campground, you're not catching it early. You're catching it late.

What prevention looks like

The good news is that the cause is usually something you can stay ahead of. Preventative maintenance makes a huge difference here:

Keep an eye on your sealants. Check that the sealant around the roof, windows and slides is still in place and doing its job.
Walk around the rig before every move. A quick look outside before you pull out is one of the easiest ways to catch a problem while it's small.
Don't ignore a small leak. A water stain inside means water has already found a way in somewhere.

If you're buying a used RV

This is where delamination hurts the most, because it's easy to miss. Buyers tend to judge a rig by how clean the inside looks, and a spotless interior tells you nothing about whether water has been getting into the walls for the last few years.

A few things worth doing:

Look at the outside as carefully as the inside — especially around slides and windows, and on the roof.
Ask whether the previous owners kept up with maintenance. A lot of the water damage we see traces back to maintenance that didn't happen.
Get it inspected before you pay. A pre-purchase inspection checks the exterior and the seals where water gets in. The Premier Package adds a moisture and water intrusion evaluation, which is exactly what you want on a rig where you're worried about this.

You can compare the two packages in Essential or Premier: which RV inspection do you need?, and see prices on the home page.

One thing we won't do

We're not appraisers, and an inspection doesn't put a dollar value on a rig. What it does give you is where the rig stands and what needs fixing or replacing — and that's usually what tells you whether the price makes sense.