Floor replacement in 16' Casita underway, help with questions

[nebraskadave]

Hi…
Been lurking prior to and since my purchase in October, now that there is nice weather in Nebraska, I’m into repair and will be looking for advice and help.
Sorry for the lengthy explanation, but figured it will help with answers.
So my “soft” floor wasn’t just my increasing waistline.
We had a 1984 Boler years ago, that we did cosmetic restoration on and used for a couple of years, then sold it. Ten years later, we were looking again, and traveled 500 miles to buy this one. Cosmetically it looked great but… floor was soft in a couple of spots, (in front of sink, and refrigerator, between floor cross braces. I was hoping that it was just the minimal bracing.
During the below freezing winter I got in the trailer and could hear some cracking (think pond ice). Not a good feeling.
I pulled up carpet and cut a couple of inspection holes through resin top coat on floor, and found bad OSB and damp/wet wood in several places. Took some of the wet wood out and didn’t see any red tint from on board water anti-freeze.
This week I have removed side dinette, microwave/refrigerator cabinet, and am in the process of cutting out the old floor. It is mush and some is currently wet. It appears that the major culprit is water intrusion from the refrigerator vent(s) and any water entering breached the front/side walls of the refrigerator cabinet, and traveled to the floor. Also the refrig. top vent (with a hose spray), allowed water to travel down the outer wall of the trailer, and past the 2x4 brace and down past the failed sealant on the refrigerator shelf.
I have searched and read hopefully all of the posts regarding rebuilding/upgrades of this area.
May have been a small leak above the refrig/micro cabinet top rivet… 2 rivets had been replaced with SS bolts by PO, No sealant and no washer other than plastic bottom cap, and one was a little loose.
Questions:
1. Suggestions for floor replacement material.
-Marine grade plywood, (can be ordered with a week lead-time)
I was ready to order today, but with a little more research it sounds like other than strength of ply, improved finish, and less voids, it’s not much different than exterior grade plywood with waterproof glue. I was thinking it had some moisture/rot resistance.
-Exterior grade plywood
-MDO , seemed interesting on this link, http://www.egyptian.net/~raymacke/TG/MDO.html
-Is there any kind of non-wood product, that would have the required strength and not have water issues?, Plastic, composite, similar to cement board, etc.?
2. Recommendation to put any adhesive on plywood to floor outer shell?, there didn’t appear to be any from the factory. I would plan on some sealant on the braces that will have the screws through them. (If I can hopefully) get the old rusty screws and large washers out without breaking every one of them now that they remain after floor was “scooped” out around them.
2. IF I decide to glass over the top, (although it makes replacement tough, and I have concern about all the holes that breach the fiberglass, i.e. Gas line, water drain, supply lines, screws for cabinet mounting blocks, screws to hold flooring to braces, etc. etc… )
What product is recommended. I may opt for a good water proofing paint, if there are suggestions.
3. I have ordered rivet kits, new refrigerator vents, from Casita.
In anticipation (of eventual) reassembly, the rivets that hold the microwave/refrig, cabinet to the exterior shell (under the slide on door molding), appeared to be ground flush on the exterior? Is that correct and what type of rivet was used.
.
4. I was surprised although the trailer is leveled, that when I closed the door I now noticed a gap at the bottom of the door along the door latch side that the cabinet was removed. With a minimal amount of pressure at the belly band (parallel to the point at which the door latch is riveted) the side of the trailer flexed enough that the door would “suck up” at the bottom LF side . Just to be safe, I did cut a wood brace and stuck it floor to ceiling, where the top of the refrig/mico cabinet “supported” the roof. Hopefully the minimal about of structure that all the rivets along the cabinets though the exterior shell provides squares that back up.
I’m sure I’ll have many more questions and welcome and suggestions/experience.
I am taking a bunch of pictures ( as ugly as this may be) that will help with explanations, or perhaps may help others with questions about how something is constructed, anchored, wired,etc. I also pulled front a/c that PO had replaced, to ensure that that wasn’t also a source of leakage. It looks ok, with the exception of some sealing that needs to be added, and I think I will add a couple diverters to help with keeping road water out….(much later project.)
I will also check with “other” forum.
Thanks and sorry again for the lengthy post.
Dave

[jen b]

On your materials point, just FYI I just had my Burro floor augmented with regular treated plywood that had the underside and edges coated with a Rhino Liner type spray. The guy who did the work has had good results with that combo. He also reattached the body to the floor and the frame with stainless steel bolts to replace the rusty screws that had been holding it all together before.

[nebraskadave]

Interesting idea, I have Line-X on a Toyota Tamoma bed, and have used the rattle can Duplicolor bedliner spray for a couple of other small projects before. I'll have to check the total thickness that would create when coated both sides. I need to make sure that the microwave/ref. cabinet still fits properly agains roof.
It looks like what was in there was
OSB =.50
resin=.10
carpet=.15 (sort of compressed)
Total ~ .75 inch

My local lumber dealer is recommending AC plywood with spar varnish sealing top/bottom/sides.
Thanks for the suggestion

[Donna D.]

Just be careful of outgassing. Sometimes things that are designed for outside use (undercoating stuff), will take forever to outgas. It's not a problem outside, but you don't want those fumes inside the trailer....

[nebraskadave]

Donna, Good caution, that's one of the reasons that I'm staying away from "pure" pressure treated plywood.

I know the key is keeping water out.. NOT making it waterproof...

With a steady rain, and no wind, I just checked and no additional areas of leakage other than the refrig vent assemblies. (yet…) with the bottom access vent taped over with plastic, I do have water dripping through the top air “exhaust” grille that runs down behind the “diverter” 2x4 and down the fiberglass wall on the interior and then (based on the trailer being very level), drops down on to the bottom flange of the lower panel… I do some sign of decay and significant discoloration of that 2x4.
I’ll try to add a pic or two that illustrates that as well.
I also sealed the top 3 holes where the refrig/micro cabinet attach to the roof , which may have been one source.
Thanks everyone.

[Vickie B.]

Just wanted to say HI Dave----I'm here in Omaha! Can't wait to see your pics!

Vickie

[nebraskadave]

Little work today, but travelled to Omaha purchased marine grade plywood ,west systems fiberglass supliplies & received casita modified refrig vent.

I'll have some additional questions regarding required fixes after my observations in the rain yesterday.

Victor at casita confirmed my earlier question regarding ground flush rivets on the cabinet to door frame but didn't have a solution for vent leak.

I will post pics soon

Hi Vickie B

Originally Posted by Vickie B.

Just wanted to say HI Dave----I'm here in Omaha! Can't wait to see your pics!

Vickie

[nebraskadave]

As time permits, I need to correctileak(s), before any additional floor work. The leak issue appears to be focused on the ref. vent/ access door area.
While the interior is stripped I had the “opportunity” to be in the trailer while there was a steady rain.
There was no wind, and the trailer is level (both ways).
1. Water was dripping down BETWEEN the louvers of the top vent (the older metal, pop riveted on) , actually entered the trailer, dropping down onto the lower access door panel and down the interior wall. The louvers are not bent or compressed (I looked at a new one at a local rv shop). It appears that the curvature of the trailer above the belly band is enough that some water shedding down the louvers enters between the louvers. It is evident that has occurred for some time as the diverter 2x4 shows discoloration from water exposure.
2. There was some water that was not draining from the bottom access vent that was entering the trailer on the RH side (from inside the trailer). The casista modification , cutting the frame and drainage tray appears to be the issue. I do have the new frame from Casita , and thought that some of the mods to the frame were from the PO, but it appears that Casita does the mods to fit a standard panel into their smaller opening.



I’ll be looking at corrections to make sure that this area doesn’t continue to be an issue.
It appears there needs to be someway to catch and drain water that enters. If the trailer wouldn’t be level, was traveling, or the wind was blowing during rain some water will enter.

The previous construction had a partial fiberglass panel over the base of ref. cabinet, with carpeted walls, siliconed to panel, and the front of panel siliconed to trailer.
This panel is where water pooled and entered apparently for some time . There were opportunity for leakage.
1. Along front of panel siliconed to trailer side
2. Along both sides of panel siliconed to carpet.
3. At interior edge of panel where water traveled under the ref. and dropped to floor.
4. Drain tube hole
5. Gas line hole
6. Panel anchor screws.

Does this all look like OEM construction in your trailers, or has someone else been in there before me?




Suggestions?
I’ll be looking at fabricating some type of drainage tray to supplement the moded bottom drain slot.
Are there flexible tapes like koolseal.com: Product Detail (Kool Patch White Patching Tape) that folks have used, where the flexing wouldn’t destroy the waterproof seals?

Thanks for all the help
I’ll try to get all the other pics loaded to Webshots this weekend and post that link.

[lars]

We're considering a 16' Casita some I'm interested in hearing how your fix turned out.

...lars

[rleete]

I just wanted to add my 2 cents in on plywood repair and waterproofing. Last year, I bought an inflatable boat in very bad shape. The rubber was okay, but the transom (the board in back) was dry rotted. Bad enough that I could easily stick a fingernail into the wood and leave an impression. Since this plywood was vulcanized into the structure of the boat, replacement would have been a major undertaking. So, I repaired the wood.

Epoxy was the answer. Standard 2 part stuff available at any home improvement store. Thinned with acetone from the auto parts store to a consistancy thinner than water, I liberally painted it on, using those cheap disposable brushes. It soaked in and disappeared. I let this cure for a full day. Then I did it again. And again. The 4th coat did not disappear, but glazed the surface. By the time it had dried, I had used up almost the full bottle of epoxy and hardener, and over half the bottle of acetone. But the transom was rock solid, and completely waterproof. I mounted a 40 pound motor on the back of that boat, and the thing held up fine.

I would not hesitate to use this method again, but I think I'd use gloves instead of bare hands! If I were to have to replace a floor, I would use this method to completely seal the wood so that, leaks or not, it would never have to be replaced again. The weight penalty would be worth the peace of mind, and the cost of the epoxy would be offset by the knowledge that it was done right, and nearly permanent.