Exposed OSB on Pup Bottom.

[vinmaker]

I am starting this thread as I was beginning to hijack the black box tread.

I would like to know of peoples experience with the OSB plywood floors that FR is currently using on the Pop ups. I have noticed that the wood is no longer coated with ProMax. It is fully exposed to wet road spray and ground moisture during storage.

I just have never saw exposed wood on the floor of a pop up before. My old Rockwood was covered. You would think a material such as Tyvek could be applied to keep most of the water out.

This is a warranty exclusion from an OSB manufacturer to the RV industry regarding the 25 year warranty.

This warranty does not cover delamination due to: (i) flood,
standing water, repeated wettings or exposure to high moisture
environments, (ii) damage occurring during transport, storage or
handling prior to installation, (iii) defects in the design, engineering
or manufacture of the RV, including, without limitation, improper
specification of the OSB by the OEM, (iv) overloading or severe
service, (v) tears or ruptures to the floor covering material, (vi)
fire, earthquake or other natural disaster, or (vii) traffic accidents,
wrecks or mishaps that damage the RV.

The clause addressing "repeated wetting" and "exposure to high moisture" is interesting.

BEWARE of water. lol.

Any thoughts on this?

Vin.

[bleurt]

So the you are covered if you always keep your camper in a climate controlled garage and never take it out in the rain. They really dotted their i's and crossed their t's on that warranty.

[pgandw]

Owned a 2000 Coleman Westlake for 7 years and never saw a problem. Coleman claimed to use a name brand OSB plywood, but it didn't look any different than other OSB plywood I have seen. Coleman literature expressly mentioned not to coat the wood product with any paint or sealant. I notice my new Rockwood A122 has the same type of floor when I get underneath it. Gets pretty dark and yucky looking from the road splash over time. But I really see no reason for it to rot unless the glue is not sealing correctly at cut edges.

Fred W
2014 A122

[KMP44]

I couldn't believe it when I first saw my 2000 Coleman popup either. Just exposed OSB. Sold it 13 years later and it looked as good as the day I bought it (the OSB, that is). Always stored outside on grass, drove in plenty of rain, but never had it out in salt/slush/snow.

Seems wierd, but it was not an issue on that camper. Still see tons of them in the cg's. I don't know if its treated with anything or just plain OSB straight out of the lumber yard. Seems like it wouldn't be that expensive for them to add a layer of wrap or some type of spray on sealant for better protection though.

[vinmaker]

Yeah. Just seems very odd to me to have fully exposed OSB on the underbelly. I would feel safer with a tyvek type material to cut down on road spray and such. Tyvek is supposed to be able to breath as well.

[exploreco]

Does yours not have a black coating over the OSB? My 2014 does. It isn't the same thing Jayco uses but I thought the brochure mentioned something about the black coating being protective against the elimates.

[BigBaron]

The OSB is exposed so the moisture can escape. If you encapsulate the OSB with a coating or film, the moisture will gather near the film/coating just as it does under a rubber mat on concrete. I used to do commercial coatings for a living so I saw this a lot on slabs that didn't have a proper moisture barrier under them, and also learned this in thermodynamics class.
The trailers with covered underfloor coverings are usually designed differently to allow any moisture to get out.
Think about it-how many 20~30 year-old pups are there that are just fine? A lot!
The black 'coating' on a lot of FR pups is actually a piss-coat of black paint just for color.
Just enjoy your pup. Yes, them FR lawyers are rat-bastards, but that's their job. My trailer's brochure says "powder coated", but the 'specifications are subject to change' clause covers their butt. The only thing that is actually powder coated are the shepherd's poles.

[campfire joe]

good information on this thread. When I got my popup last May, I got under it to grease the lift system and saw the osb board, and thought that it would rot after a while. Thought about putting a coat of primer paint on it, lucky I didn't. Mine also has a dark stain on it.

[phillip252]

I too also started to put some type of coating on the under belly when I saw it, pup is stored out in the open, under covered top and covered up. ?????

[pgandw]

Some things I learned from being around and involved in building and repairing wood and plywood boats:

- paint, especially household latex paint, does NOT STOP movement of moisture from atmosphere to/from wood. It merely slows the passage of mositure down. Even marine epoxy and polyurethane paints don't stop passage of moisture, but they pass it slower than latex. And the passage of moisture is in many cases a good idea because it allows the wood moisture content to equalize with ambient humidity.

- where equalization does not happen, and the wood gets saturated with moisture, dry rot can occur. Plywood, osb, chip board, and other glued sheet wood can have glue give way over time due to saturated wood fibers, causing delamination. This can be caused by swelling of the wood fibers or the glue dissolving in the presence of water.

- wood shrinkage from uneven drying out or getting too dry causes warping - commonly seen at big box lumber yards. Or in the case of wood furniture, joints separate because the wood shrinks too much. Stains, shellacs, varnishes, and paints, because they reduce the rate of mositure passage, often help prevent warping or joint separation because the wood never gets to peak dryness of the atmosphere.

- sealing one side of plywood with expoxy resin or other truly impervious coatings will likely cause warping and/or rot because of the now uneven mositure content. Wood and wood products should be able to breathe, or need to be totally encapsulated.

- totally encapsulated plywood, commonly used as a core in fiberglass boats, is subject to being compromised and eventually rotting from every unsealed or improperly sealed hole in the encapsulating material.

I see many new houses with chipboard exterior walls sit through extensive thunder storms before they get their final exterior cladding. I have never seen any damage unless the wood products sit in a puddle of water.

I have never seen the untreated OSB floors or beds (on PUPs) rot out. It might be possible, even likely, if water was allowed to pool and sit on the OSB while the camper was stored.

just my experiences, yours may differ
Fred W