The Perverbial Rotted Floor due to Water

[Robo]

My number one sealant where you do not water to penetrate is 3M marine sealant. I would use it to seal up that front. It does take a full seven days to fully cure, but it will be sealed.

https://www.amazon.com/3M-5200-Adhe...9038361&sprefix=marine+sealant,aps,232&sr=8-4

Thanx for the input!

 

[Springhaven]

We have recently run into the same issue and are debating having someone fix it for us or try it ourselves. We have the MPG 186 so the small floor plan has to make it easier. But the slide letting water in has been a sad turn of events in the last year.

 

[ParkIt]

Stumbled on this post and very helpful as I suspected and confirmed today the larger entry slide floor is reading moisture on each outside corner. Sure enough, there are 2"x2" 'sags' on the underbelly corners and I can feel how wet it is. Gives me an excuse to get rid of the MDF and use plywood though I need to research if 1/4" plywood with 1/4" backer board (hardi-back) will be too stiff or too heavy, hope not, it's been my go to material on any residential construction.
Anyone ever try using that method?