Help rotting floor

[beach momma]

We are totally new to pup's and have just purchased a used '98 Mesa. It appeared everywhere to be a cream puff in immaculate condition but...... today while greasing all the cranks in prep for our maiden voyage we found that there is rot under the trailer on the ply bottom. It appears the fridge which was recalled per the previous owner had a condensation problem which lead to the rot. It is not very big and has been dry for some time. We just wonder should we try to cut out the 4" by 8" section and replace or as a former sailor should we get a marine epoxy and inject into the now dry rot to harden and move on? We are going to give the underside a good coat of marine varnish or water sealant. Can't believe these things are just bare wood. Any suggestions anyone? Also I'm now paranoid about using the fridge, anyone else had problems with condensation? We are down in South Florida where the humidity is unbelievable.

[austinado16]

You'll want to leave the bottom uncoated.  They're apparently designed that way so the wood can breathe and it keeps them from rotting.

I'm not familiar with the epoxy injection trick, but since it's in a place where you won't be walking, it sounds good.  Heck, you can always come back and cut out the section if you don't like how it's holding up.

You might consider popping up in the driveway or back yard, etc., run the fridge and see what happens. Check the seal on the fridge door.  Maybe you only get moisture after shutting off the fridge?  You can test the fridge door seal by closing the door on a dollar bill and then trying to slide the bill around the door.  Anywhere it can slide is a bad area of the seal.

[mike4947]

I'll second the do not attempt to seal the bottom of the Structure wood floor; and the use of the epoxy rot repair compound.
The flooring is designed to be wet and dried multiple times, but not to stay wet. "sealing the floor" is next to impossible due to the areas at the edges and over the frame members. These areas will get wet and wick into the "sealed areas" and not evaporate. Then those areas WILL dry rot.

[wavery]

I'll 3rd the motion not to coat it.

I'm an old sailor also. I built and repaired boats for years. My initial reaction to the uncoated wood was the same as yours but I soon learned that I was wrong.

That is not plywood. It is particle board so you have no continuous strands of fiber for any epoxy type product to adhere to. Whatever you put in there may just fall out over time.

Wood rot is a living organism and it will spread over time. It's best to cut it out. If it is in a non-stress area, I would just cut out a perfect square, glue in a replacement piece of an identical size, then glue & screw a larger piece over it for reinforcement.  

[ScouterMom]

My vote is for no coating, too.

My camper is over 35 yrs old, and also had some badly rotted corners (the lifter posts channelled water right into the campers and rotted out the floor - the posts fell THRU the floor and cut the cables!)  

I also had another 70's camper once, and I've tried that injectable epoxy for hardening wood rot  on it.  It will work temporarily - but it makes the wood hard and brittle - and very difficult to work with later (can't drill screws into it, hard to cut, etc - also, the rotted pieces tend to break  away - like chipped nail polish or broken plastic)

With the current camper - I cut out the rotted pieces, past the rot at least 2 " - and put a new piece of plywood in, backed on the underside by another piece about 2" larger than the hole, so I could screw it into the old floor from underneath.  then I caulked the seam (mostly to hide the seam so that it wouldn't show thru the linoleum)  as I planned to put new flooring down.

However we used the camper for more than a year before I got around to laying the new floor, and the patches held up great, even with us walking on them.  

Most people are surprised to find that there is no paint, treatment or coating under the floor of these campers - but  really, they DO NOT need to be coated, they are much better off open to the sir to dry out.  The rest of my floor is in great shape for it's 35 yrs, and only a great deal of standing water in those back corners caused it to rot there.

Patch the rotted spot, and leave the rest alone - it will last you a good many years!

laura

[beach momma]

Thanks a lot guys! We use the same particle board for hurricane prep as under the camper floor and always ditch it at the end of the season. We were told it weakens when wet. Guess Home Depot have done a great "education" job. We will cut out the spot as it up against the side wall under the cupboard area it may be tricky to get it out but not impossible. And I will run the fridge and see if the coils get condensation again. We can't wait to try the camper out, I'm sooooo excited to be off the ground and I'm sure our crazy parrot will love it as well.

[ScouterMom]

If it's condensation on the fridge coils that was causing the moisture problem - you might look into some of the mods on here that other's have done - adding fans to circulate air behind the fridge. Many people have done this mod, and it doesn't look hard - basically they install a small computer fan or two and it increases the efficiency and cooling power of your fridge (as a side benefit, it could reduce the moisture back there, too)

I use a small electric 'dorm' fridge, so I have not done this mod myself - but it doesn't look that hard!


As for getting the floor wood out along the edge, you may have to chisel some pieces out - as they are probably going to be between the frame and the body of the camper - but in that end, that's good as you will have the solid camper frame to support the new piece.  

laura

[PattieAM]

You might want to read up on 'Structurewood' (and there is a website), and it's need for breathability.  Many confuse it with the particleboard on the market.

Structurewood is not to be coated/sealed......

If condensation from your fridge is an issue, you might consider the mods of adding a fan behind your fridge to improve air circulation.