Soft floor

[Riverpark Eric]

Recently my 1988 22' Odyssey (bathroom behind the drivers seat) has developed a soft spot between the bathroom door and the side door. I haven't peeled back the floor runner or carpet to check it out...slightly out of fear of what I'll find, and slightly because I'm also remodeling our kitchen! It's certainly not soft enough to be a danger, but is definitely soft. Where do I start, and what the heck do I do when I get there?

Thanks.

[Lee & Joan]

Had the same thing on Sunrader in front of the kitchen area. Got under the frame and everything looked good. Tore out the floor and replaced with stiff underlayment then Oak flooring, both layer glued and screwed. Still is spongy there. But no squeeks anymore when walking across area. Probably not worth the time but know now that nothing was rotten to begin with.

[Riverpark Eric]

Had the same thing on Sunrader in front of the kitchen area. Got under the frame and everything looked good. Tore out the floor and replaced with stiff underlayment then Oak flooring, both layer glued and screwed. Still is spongy there. But no squeeks anymore when walking across area. Probably not worth the time but know now that nothing was rotten to begin with.

So what was the cause? I'm confused.

[Lee & Joan]

I am still somewhat confused as well. What I found under the original plywood was a semiporous insulation type board. It would not hold screws well so the plywood was free to move up & down. The original glue was sparce and had long ago let loose. I used full coverage glue and way more screws. I think the underlayment is supposed to be a spongy insulation.