RV sidewall bubbles and delamination: what it is and what it costs

A bubble, bulge, or soft spot on an RV sidewall is a sign of delamination, separation between the outer skin and the material underneath it. It is a structural issue, not cosmetic, and it is worth having assessed before it spreads.

Check this first (five minutes)

Press gently on the area. A soft, spongy give under light pressure, compared to the surrounding solid wall, confirms something has separated underneath.
Look for the likely entry point nearby. Delamination almost always starts at a compromised seam, seal, or fitting: a window frame, a body seam, a roof edge, or an attachment point. Check the seal condition there.
Note the size and shape. A small, contained bubble is a very different repair than a bulge spanning a large section of wall.
Check if it is spreading, if you have noticed it before. Comparing to an old photo, if you have one, is useful.
Do not press hard or attempt to push it back flat. That can crack the outer skin and make the repair worse.

What is usually wrong

What you find	Likely cause	Fix and cost
Small, contained bubble near a seam or fitting	Early-stage water intrusion at that seam	Injection repair $400 to $1,200
Bulge spanning a larger section	More advanced delamination	Assessed on site; larger repair
Bubble near a roof edge	Water tracking down from a roof sealant failure	Fix the roof source first, then the wall
Soft spot near a window	Failed window seal letting water behind the skin	Reseal the window, then repair the wall
Crazing (fine surface cracks) with no soft spot	Cosmetic gelcoat aging, not delamination	See fiberglass repair, lower priority

Those ranges are from the pricing page, on top of the $75 to $150 trip fee and $125 to $190 hourly labor.

Why the source matters as much as the bubble

Repairing a delaminated section without finding and fixing the water source that caused it is a temporary fix at best. In Kern County, the most common sources are a roof sealant failure that lets water track down inside the wall from above, or a window or body seam seal that has hardened and cracked from years of sun and heat exposure. Both age the same way sealant does everywhere on the rig: UV and sustained heat, not rainfall volume, is what breaks them down here, and the valley’s occasional wet stretch is simply what exposes a seal that already failed months or years earlier. We trace the source before repairing the wall itself, because sealing over an active leak just delays the next bubble.

What to expect on the call

Photos of the bubble or soft spot, and of any nearby seam or fitting that looks compromised, are worth a lot before we arrive. We work on site across Bakersfield, Oildale, Rosedale, Shafter, Taft, Tehachapi, and the Kern River Valley.

Frequently Asked Questions

What exactly is delamination?

Separation between the fiberglass or aluminum skin of the sidewall and the substrate underneath it (usually foam or wood), most often caused by water getting behind the skin at a compromised seam or fitting. It shows up as a bubble, a soft spot, or a slight bulge in an otherwise flat wall.

Is a small bubble an emergency?

Not usually urgent in the sense of needing same-day attention, but it should not be ignored either. Delamination tends to spread once water is behind the skin, so earlier repair is smaller and cheaper than later repair.

What does delamination repair cost?

Small, early-stage delamination is often a $400 to $1,200 injection repair. Larger areas or structural sections require an on-site assessment before we can quote, since the true extent is not visible from outside.

Can heat cause delamination on its own, without water?

Not typically on its own, delamination is fundamentally a water-intrusion problem. But heat accelerates the aging of the seals and sealant that are supposed to keep water out in the first place, so a hot climate can indirectly speed up when delamination starts.