What is causing this...?

My wife noticed these bumps in the ceiling of one of our slides. I tried to peek up there, but I can only see the insulation. It's a 2008 Carriage Cameo. We did have an attack of ants in the past few weeks on the opposite side of the rear of the RV. We used some boric acid to discourage the buggers from returning. I sprinkled some in the electric outlet are and around the wheels, jacks and stabilizers...anything that touches the ground basically got a ring of boric acid around it.





Any help is appreciated.

If it was new paint, I'd say some moisture was between the paint the the drywall ceiling.

That kind of bubbling sometimes happens when the ceiling is wet or damp and gets painted over.

But definitely something to do with moisture ... if this is the slide ceiling, you might have some water leaking in under the roof and just penetrating the ceiling.

Hate to say that - because finding water intrusion is sometimes very tough.

OR, it looks like the ceiling was not sealed properly before it was painted.

How old is that paint? Did you paint it yourself?