What is this?

[Advonwheels19]

Looking for some help please. Over the summer we noticed some bumps on the wall in our 2017 Whitehawk 27 DSRL. These are hard and sharp/pointed to the touch. This seems to be getting worse. It is located between the window and closet on the passenger/exit side of the camper. This is the only location and there doesn’t appear to be any of the “typical” signs of water - no staining, wallpaper peeling or lifting, or water on ceiling. The area was not wet following 4 inches of rain from Henri or 2+ inches from Ida.

Really hoping some of the more experienced RV’ers on here might know what this is, if I need to be concerned or is it cosmetic, and what to do about it?

Image attached. Thanks in advance!

[Grumpy]

Unfortunately usually a sign of moisture in the wall.

[THE MEEKER]

X2! It is mold spores caused by water seeping in that area of the wall.

[TWP723]

X3

[Jagiven]

There have been a few posts like this in the past year or so. I have not heard if anyone has truly determined what is causing them. Being a 2019, I cannot believe it is outgassing of the adhesive at this point.

The wallboard, is a vinyl coated plywood. Kind of like wallpaper, but on an industrial scale, with an industrial grade adhesive, that is permanent. I do not believe any moisture can penetrate this vinyl. So any water behind the vinyl, will not be scene. If it is moisture, the adhesive that is well bonded to the wood will not be move, and may even break pieces of the plywood off with it as moisture swells the area. The wet wood maybe pushing out on the vinyl, and creating this hard mountains. This is only a guess.

Have you taken a pushpin and tried popping one of the smaller bubbles? Any moisture come out? You can buy a moisture probe that will give you feedback.

Every hole in the TT, has some type of sealant, and they all start to fail as soon as they are applied. I would do a very thorough inspection of your exterior. Start at the top and work your way down. The roof sealant failures are very easy to see. Marker lights, wall connections and windows are a bit harder to identify. Check every caulk joint.

[Jamnpete]

Our 2015 Greyhawk 29MV has been a good rig, there have been some minor issues, but most have been resolved without too big of a headache. Although, over the last two seasons, there's been a mold/fungus growing through the side trim molding. Body shop guy at Camping World, knew about it right away before I even told him it was a Jayco. He says the Jayco crew is very inconsistent with their caulking methods, as in not enough caulk around those trim strips. He recommended replacement, currently waiting to hear from Jayco on availability. Anyone else see any of this, photos attached (I hope).

[Advonwheels19]

Originally Posted by Jagiven

There have been a few posts like this in the past year or so. I have not heard if anyone has truly determined what is causing them. Being a 2019, I cannot believe it is outgassing of the adhesive at this point.

The wallboard, is a vinyl coated plywood. Kind of like wallpaper, but on an industrial scale, with an industrial grade adhesive, that is permanent. I do not believe any moisture can penetrate this vinyl. So any water behind the vinyl, will not be scene. If it is moisture, the adhesive that is well bonded to the wood will not be move, and may even break pieces of the plywood off with it as moisture swells the area. The wet wood maybe pushing out on the vinyl, and creating this hard mountains. This is only a guess.

Have you taken a pushpin and tried popping one of the smaller bubbles? Any moisture come out? You can buy a moisture probe that will give you feedback.

Every hole in the TT, has some type of sealant, and they all start to fail as soon as they are applied. I would do a very thorough inspection of your exterior. Start at the top and work your way down. The roof sealant failures are very easy to see. Marker lights, wall connections and windows are a bit harder to identify. Check every caulk joint.

Thanks for this. I tried a thumbtack and no moisture, so I went a little deeper and sliced one with a razor. Dry, but as you said there is a material pushing through from the back. It is not wood, but seems more like a cork or pressed paper substance. Either way, I suspect you are spot on and water is getting behind the vinyl.

I thought I did a pretty thorough inspection for potential leaks in the Spring (and sealed a few) but obviously missed something. Will be doing another inspection top to bottom as suggested.

Thanks, again, to all for the help!