Floor soft spots

[Habenero]

I have soft spots in my floor and they are growing. No water. One RV tech said the styrofoam between the plywood boards has compressed and I will need support braces installed.
I'm interested to hear if anyone else has had this issue. 2018 Cruiser Aire.

[ugauga]

Originally Posted by Habenero

No water. One RV tech said the styrofoam between the plywood boards has compressed

Did he pull the vinyl flooring and plywood up to verify that or is it just so he can get you in, start working and call you saying he will need to redo the floor after all and it will cost 5x his initial estimate? Any particular areas you have these soft spots at? Did you see the underlayment and it looks nice and bright with no water stains?

[TexSon]

Yeah, I had soft spots on my Zinger and it turned out the cellar door seals were shot, let water in, and soaked the fiberglass insulation which in turn rotted the plywood flooring. I had to cut out a lot of flooring, remove all the water logged fiberglass and replace it all, including new flooring, vinyl, and I used spray foam insulation since it is fire resistant was well as repels water better then fiberglass. I also had to replace some of the framing. Good luck, but be prepared to do a lot of work!