The inevitability of slide floor rot?

[Mukiwa]

Hi all,

I own a 2016 Forest River 5th wheel (Crusader). Common to many 5th wheels and travel trailers, (and maybe other RV classes) the slide floors are made of oriented strand board (aka particle board). I have already had to replace part of the bedroom floor board due to rot from water.

The exterior of the slide floors are covered in a thin, black non waterproof tarp material with no barrier between the covering and the board. The construction of the slides ensure that any rain falling on the slide side will inevitably wick into the board and cause rot.

This appears to be a very common problem with medium to low end travel trailer and 5th wheels.

Has anyone found a practical way to proactively prevent the inevitable slide floor board replacement? I'm not looking forward to spending $1,000s on fixing what looks like a blatant design flaw!

[R.Wold]

there are good water proof, almost everything proof, industrial coatings that even qualify as secondary containment for hazardous materials that can be pained on, available at Kelly Moore and other comercial coatings dealers.

If water can get in on top of the slide floor this wouldn’t work, but if the problem is exterior, maybe so. Paint it with the stuff (don’t recall the trade name) or something similar, caulk the edges with something really resistant and you might buy yourself quite a few years.

[hamm2018]

I check the caulking on the slides every quarter, during a quarterly preventive maintenance schedule I have created.
I do a weekly, monthly, quarterly, semi-annual and an annual maintenance schedule. During the time I spent in the Navy we used a system known as 3M Maintenance System. My system is not as intense as what we had in the Navy, I don't required specific grease, or other such requirements, as doing it step by step.

[Gary RVRoamer]

Well, cheap construction always has drawbacks, and water leaks coupled with susceptibility to water damage are two of them. I suppose you could tear up the floor covering and seal the wood with any of several water-resistant primer/sealers, but that seems extreme. I think it's more practical to just keep a sharp eye out for the beginnings of water intrusion and fix the leak at the source. Only do the wood subfloor sealing when/if intrusion makes it necessary.

[Mudfrog]

May not be easy but I'd see about getting rid of that "black non waterproof tarp material" and replace with something more water resistant.

My first thought is something like the 1/8 inch corrugated plastic material that many RVs have. I wouldn't think it'd be too hard to work with. Maybe in conjunction with an automotive spray on undercoating.

[twogypsies]

The first thing to do is to get rid of the water leaks otherwise you'll always have a problem. Good luck!

[ctgt]

Best to just keep an eye on the exposed bottom of the floor. On most there is a piece of metal trim that wraps around over the side panel and bottom edge of the floor, basically a piece of outside corner trim. Be sure to maintain the bead of sealant. The bottoms are not made of particle board. Never seen one that was. It is usually oriented strand board, OSB, and that is an entirely different material than particle board.

[keymastr]

OSB is junk too. If you have to replace the floor use marine grade plywood. More expensive but if it gets wet it does not swell and crumble apart.

[R.Wold]

OSB is sub-optimal compared to marine plywood, but I’ve seen it hold up unfinished for five years exposed to weather on a shed in an area that gets a lot of rain and snow. Turns grey and starts to “disorient” but it’s pretty tuff stuff.

I really thing the solution here is to remove the cheap fabric “protective covering” and use a good industrial coating, or even a few coats epoxy garage floor paint from Home Depot, and some good butyl rubber or other 30- 40 year caulking on the edges, and it will be wordy free for the life of the trailer, unless water gets in from above.

My daughter had a 2018 FR Salem that had a leak around the door that entered the wall and completely rotted out several square feel of the floor around the entry, so definitely something to stay on top of, but that doesn’t seem to be the issue here.

[Cat320]

We've had four RVs with slides, never had a floor problem.

[R.Wold]

Originally Posted by Cat320

We've had four RVs with slides, never had a floor problem.

Any of them built by Forest River?

[Mukiwa]

Thanks for all the useful advice and suggestions. I peeled off the black plastic underneath of the bedroom slide and sure enough there's evidence of water damage, though the board seems reasonably sound. Ive decided to initially treat with a low viscosity epoxy, which promises to restore lost strength and also render the board waterproof going forward. Product is called PC Rot Terminator and is recommended for marine solutions. Following that i will paint with a black rubberized coating to match the original look. Time will tell...

[LanceKeys]

I replaced a section of my slide for damage caused by this very thing. I went back with marine grade plywood, coated with a sealant and wrapped in the same plastic stuff as factory. Maybe it will last, maybe not, but my repair is better than it was from the factory.

[R.Wold]

Originally Posted by Mukiwa

Thanks for all the useful advice and suggestions. I peeled off the black plastic underneath of the bedroom slide and sure enough there's evidence of water damage, though the board seems reasonably sound. Ive decided to initially treat with a low viscosity epoxy, which promises to restore lost strength and also render the board waterproof going forward. Product is called PC Rot Terminator and is recommended for marine solutions. Following that i will paint with a black rubberized coating to match the original look. Time will tell...

I think you’re on the right track here