What are the floors made of circa 2002?

[Rocketgirl]

I have a Sunline Lite 2002 T1950. Further exploring some soft spots in the floor last night, we took up some of the vinyl and first noticed a "large chip" sort of plywood which was where most of the soft rot was located. We scraped through some of the rot, and there appeared to be a harder, solid board underneath, that was not soft chip-board like the top surface. Any idea how many layers of board there are in the floor?

My initial fear was that if the rotted board was the primary toilet support and was close to the toilet, the toilet could push through and collapse if someone large sat on it. However, if the soft rot is only on the surface board, and there is a more solid structure underneath, maybe the soft spots are not so lethal and no one will end up in a horrible toilet sinkhole accident any time soon .

In the end, I probably will have to replace the floor anyway to avoid incident (real or imagined), but it would still be helpful to know how many layers I am going to need to deal with. Kind of short on cash for the moment, after my big travel trailer purchase, and if I could postpone the work for a bit without any incident that would cause traumatic dry-heaves to a germ-o-phobe, it would be nice!

(I have a separate thread for toilet replacement, this is just about the floor.)

Andrea

[Gene]

The floor is a single sheet of Oriented strand board (OSB) laid directly on the metal frame of the trailer. The walls are built on top of that.

Some info about OSB: Oriented strand board - Wikipedia, the free encyclopedia

[bunjin]

Where exactly did you do this exploration? Was it next to the toilet? If so the hard surface you refer to may be the Black water tank. The tank is made out of black ABS plastic. Pictures would help.

[Gene]

My previous post was not quite correct. There is also an underbelly material called Darco on the frame and the OSB is on top of that.

As Lynn (bunjin) said, pictures would be helpfull. It could be that just a layer of the OSB is rotted.

[Rocketgirl]

Here is a closeup of the osb board rot scrapped away; underneath there seems to be a harder board, with a solid continuous texture, unlike the osb.

[Gene]

Interesting picture. Since OSB is "laid up" in layers with resin at the factory, I wonder if you just found the outer layer and it had a higher resin content. The stuff remaining in the picture looks like it is free of mold. I wonder if something like "Rot Doctor" would build that back to full strength. There are many here more qualified than me to offer an opinion on that.

[Urbanlex]

Originally Posted by Gene

The floor is a single sheet of Oriented strand board (OSB) laid directly on the metal frame of the trailer. The walls are built on top of that.

Some info about OSB: Oriented strand board - Wikipedia, the free encyclopedia

Hello Gene,

Was just curious why they would use this on the floor ? Doesn't this material act like a sponge with water splashing underneath onto it and all the damp conditions when camping or parking the trailer on earth for long periods of time? Is this what most factories or the handy man use when restoring their RV floor? Not the first choice of material I would pick for the floor, but what do I know? My trailer has the same material in it and i'm about ta fall through the floor

[Gene]

Often OSB gets confused with particle board which is basically sawdust and glue. Particle board is heavier than OSB and not as strong. OSB is usually a bit more rigid than plywood and, as I understand, is about the same weight. Since OSB can be manufactured in almost any size it can make a one piece floor in an 8 foot by 24 foot trailer with no seams. I think an 8 x 24 foot sheet of plywood would be much more expensive than OSB and not as rigid given the same thickness.

The downside, as you found, is that it can get soft if it stays wet long enough. Plywood can be waterproofed quite well but OSB, even with the resins use to make it, can not be made as waterproof as plywood. Both of them will fail (get soft) if kept wet long enough.

I don't think the trailer designers / builders could imagine all the ways water can get to the flooring. I guess they expected that Darco fabric sheet underneath the floor would keep the water away from the underside.

[Urbanlex]

Yes I was one of those who confused OSB with particle board n as mentioned "What do I know?" Yes I am new ta this but have learned that water leaks are one of if not the biggest problems with RV's. I am looking into spraying my roof maybe the entire camper with rhino? I hear it last the lifetime of the trailer? I have ta do my research first and see what my options are?

Thanks Gene very interesting and knowledgeable information.

[Rocketgirl]

I saw your posts going back and forth and I wanted to add some of my observations. I did remove the soft spot when it went all the way through to the support beam. I was going to try to slip my iPhone camera in there to take a panoramic picture inside (with a safety tether of course!), but the hole was not big enough and I did not want to take any more structural integrity away by making the hole bigger at this time.

I did experiment with drying the floor out with a dehumidifier and hair dryer. I then put some of that rotten wood hardener (bought it at Home Depot, don't have it with me right now) in multiple coats on the remaining soft/stained floor. After letting it dry a few days, I have not had a moisture problem since and the floor seems to be fairly rigid and holding together well.

I put a piece of cut plywood over the whole bathroom floor with a bathmat on top, and I don't feel any issues. However, I am a smaller framed person and I am reluctant to let a larger person use my facilities.

I have NOT used the shower since I began this work. I like long hot showers in the bathhouse anyway, so this is a lower priority and I have an outdoor shower. But since I have not had any moisture in there since I did the repair, this rules out the roof (we have had some hard rains, and everything stayed bone dry) and the toilet. I have not had the holding tanks topped off, but I am using them.

I'll post again if I find the time to explore more about the shower and maybe find a way to get some internal iPhone flash photos.

[OhhWell]

I'm probably confused but the picture you posted looked like the solid wood suface was the floor joist under the OSB. There was not an aluminum frame under our 2002 when I cut into the soft floor in our bathroom.

Scroll down a bit in this thread

Bathroom Floor Repair

And you will see some pics with a bit of the OSB removed.