Soft floor discussion (pics and steps to fix included)

Hey Wing!

I hear you....I had a chemistry teach that would get pissed if you said "Styrofoam" or "Kleenex"....heaven help any kid that mixed up "transparent" and "colorless".

One of my first calls was to a company called Rot Doctor..they sell a product that is supposed to seal up wood and stop rot...I was telling him my issues and he said the following...
"High density foam is usually polyurethane-based, in which case CPES will have no effect on it. CPES is only incompatible with Styrofoam."
So I called Aerolight customer service to see if it was extruded polystyrene vs. high density foam....they confirmed that the floor is not extruded polystyrene...the walls are a different story as they do contain extruded polystyrene.

I'm not a chemist, so I don't I really get what all this means, but I ordered a bunch of Rot Doctor stuff hoping it will help get the job done (and not melt the foam at the same time).

T.

Styrofoam is actually a brand name, just like saying scotch tape. The fact is they are all extruded polystyrene foam boards, panels, whatever (which is way different than the material that is commonly referred to as a "Styrofoam cup" or other similar materials). They all come in different densities which is why you seem to make a distinction between "Styrofoam" and "high density construction foam". Sorry if I confused you by using the term Styrofoam instead of foam panels, boards, whatever; it's like the scotch tape thing.

use some type of glue recommended for the foam material perhaps such as liquid nails. do not use gorilla glue.
bumpy

The flooring isn't styrofoam, it's some form of high density construction foam....styrofoam is in the walls though.

I'm going to take the door off an get that rotten board out, and cut out the really bad plywood...then I'll know if there is (supposed to be) a stringer anywhere near there...I have to admit that it's really weird that the board just ends with no support around it....all I can figure is that the plywood and the 2x4 were glued together at some point in time, but once the rot got to the board it went south quickly.

Re: construction details....all I wish is that they would of used marine grade plywood instead of this cheap stuff...I bought the aerolite thinking I was getting more aluminum and less chance for rot....little did I know that most campers have the same weak link.

T.

I know that there is a water activated gorilla glue you can use to bond styrofoam to wood (you actually have to wet the surfaces to activate it). I don't really know how good the bond is. And the glue ain't cheap. I have used it before and it is suitable for my purpose but if I were you, I would test the bond before I went ahead with using gorilla glue. There may be others, I don't know.

This brings me to a interesting thing I will point out. Some people disparage the foam/wood laminate type construction. I will tell you first hand that you can make some amazingly strong structures with this type construction that are also amazingly light weight. There is nothing wrong with this construction method as long as the bond holds.

It appears from the video that you have a loose ribbon or stringer near the door (where the cabinet used to be). A joint may be cut in that area. I believe once you get the plywood up, you'll see where you need to attach support for the steps.

Typically, mfg's use an adhesive that doesn't interact with foam to bond the plywood to the foam and any joists below the plywood.

Thanks for replying.

The frame for the steps is attached to the trailer frame, but it's not a very sturdy mount. It's put onto the frame with 1/4" self tapping screws, one on each side.

I'm pretty sure that the majority of the strength for this sucker is coming from the flush mount bolts that go straight down, near the front door.

Sorry, I can't see the video at work. The steps should also be attached to the frame for strength. When replacing our steps I used lag bolts onto the wood above, self-tapping screws into the frame and will be welding for added strength (it was welded from the factory). The majority of the strength should be coming from the frame mount and I used the lag bolts to really just hold the new steps in lace before I attached to steel.