Excuse my ignorance (Floor repair question)

[59toaster]

Ok I think I have read every post on replacing rotted floors. Almost every picture I have seen had something that struck me odd and it isn't clear to me is why people are doing it this way.
As I have picked up the traller is assembled this way. Belly pan,
Frame, insulation, 5/8's ply deck, U-Channel bolted to the Ply, Shell rivited to the U-Channel.
Now I'm confused here. The U-Channel is bolted to the Deck so why is the U-Channel being seperated from the shell? Seems to me you could unbolt the U-Channel and lift the body off at that point leaving the u-channel atached to the shell and save having to drill out a zillion rivits. Is the rivits that hold the belly pan to the trailer the same as the rivits that hold the shell to the U-Channel?

Next Question is sealing the floors to help prevent rot in the first place. What's wrong with taking a few pages from wood boats and using an epoxy or even a fiberglass resin and coating the Plywood with it to get it as sealed as possible? Seems to me that many leaks go unnoticed or are hidden in such a way that you don't find them till it's too late. Taking extra steps to make the deck as water proof as possible. Even a coat of exterior latex thined out some to get penetration would help I would think. I have a little wood deck enclsed utility trailer I built and I painted all the dekc on the botom with exterior and it's holding up great even with it parked in the dirt 95% of the time.

Next is seal the wood and go one step farther if your having to pull the shell off to repair the floor. Put one peice flooring over the whole deck BEFORE you bolt the u-channel back on. The stuff is cheap and durable. Yes it would add a little weight but I'll take a little weight to prevent having to repair this floor ever again. Once you have the u-channel bolted down it would form a bit of a seal and roll the excess under the deck and staple it off. RTV all the bolts and the holes to create a seal. That way any water that does get in has no way to get to the wood. Even if you planned to put down a Purgo or something this would be a worth while step to prevent moisture from above getting into that ply deck again.
Is there a flaw I'm not seeing to doing it this way?

[Chas]

The U-channel has also got a flange that is hooked onto the edge of the flooring. Looks like a U from the top but also has a J-leg which goes down and turns back in. Not around the entire perimeter but only in the straight sections. It strengthens the outside edges of the plywood flooring and makes for a stiffer bottom track. The bottom track is the foundation for the entire shell.

I think we are all in agreement as to the wood flooring being one of the weakest points in our vintage units. It is the main reason I have chosen to use treated plywood in the floor repairs on my Overlander. Pulling a 24' shell would probably be impossible so I am content with just patching up what rot I've got. I understand it can also be a nightmare getting it back on correctly.

Chas

[59toaster]

Ok then that makes sense. I was looking at williamhenshels pictures of his floor redo and he had some close up of the front U-Track and you could clearly see the Ply on the edge. Didn't see any shots of the peices down the side's. Well I was holing to save a little work but I guess not.
I'm not even sure how bad the floor is in my 59 yet. I know it's done under the toilet area. I found some rot up in the nose. So those two areas I can live with just patching. I noticed on the curb side that the sin is a little wavey and read that it's a sign of bigger problems wit hthe floor. Another Problem is I know my Father-in-law has had to patch the floor in other areas like around the door. I may get up the floor covering and find patches everywhere and be better off replacing it all in one shot.
My ace in the hole is a buddy with a awsome shop at his home. Might even get lucky and be able to do the repair inside. He has not one but two 2 post lifts (one inside and one outside). I should be able to put some 4x4's through the window openings and lift it like that just enough to pull the frame out. He also has two Mig welders that make My Mig look like a toy so I can handle any major problem over there. I also have a ton of friends that love projects and with their help knock it out in one weekend and drageit home to reinstall the insides.

I'm also up in the air as to wether I even want to put the inuslation back under the floor. Seems to me that's just agrivating the problem by when it does get wet holding moisture longer.

[BobbyW]

Not to get into another argument about this point again, only more discussion, but treated plywood CCA (chromium, copper, arsenic) is not to be used in closed environments due to the out gassing of the treatment chemicals. This was in the news again just last week in regards to playground equipment. They are talking about tearing out all this public playground equipment all over the country. The manufacturers themselves recommend you cover treated wood picnic tables with plastic table clothes to prevent posssible poisoning. I have posted links to several papers on this subject in other posts on this subject.

Sealing the floor reduces the wicking effect that the floor provides in removing moisture from the interior of the trailer. This is from Airstream. As the interiors are so tight (new trailers) the moisture has no way to escape but through the floor. Again, according to Arstream.

From Thompson engineering, (I made several calls to them on this) their products are for exterior use only.

The best prevention is to make sure the roof vents, furnace vents, windows and fresh water filler are properly sealed. And don't forget the door seal. These locations are were 95% of leaks come from. If these are maintained, the floor should last several decades.

Best regards;
-BobbyWright

[John]

You're majorly lucky/fortunate to have a friend with such an awesome space available to do this job.

4X4's stick together eh!!!!

I did a complete rebuild(just a frame on 4 jacks) of a 73 C-10 in my one car garage with a small utility room. Had one hell of a good friend donate many weekends(Friday 5pm - Sunday midnight) and I wouldn't have done it with out him!!

If you have these resources available, I'd go for a complete new floor. As far as material, I don't have the experience to share, but will say that last year they redid all of the playgrounds in my county.

Enjoy-John

[59toaster]

Yeah good friends with Great shops is a good thing
Talked to him about it today. He was cool with it and just wanted a weeks warning to make sure he didn't have anything else planned. Hope to have some time in about two weeks to drop the belly pand and pull up the bath and see what I'm really in for.

Yeah I have a 74 Blazer body that is mine for the taking. Supose to be pretty solid. No running gear but I have a 3/4 ton 82 long bed with no engine I could get cheap. Make a pre runner with the combined parts and drop a LS1 in it.

[Chas]

Bobby,

I understand the current concerns with the cca treated lumber. I saw a segment on some news program about a couple who built their retirement cabin in the woods and ended up sick as a dog and with a useless house. Just like everything else, the good stuff ends up being bad for you, asbestos, urea foam, fried chicken, etc. I have only patched a couple of square feet at the perimeters of my Overlander and will probably not be eating off of it so I should be o.k., I just don't want to be patchin' it again!!

Chas

[Paul Mayeux]

Having extensive experience with wood boats I can appreciate the desire to seal the wood floor. Especially after replacing a section under the front window in my Overlander. There is a product that I would highly recommend to seal any wood product. Clear Penetrating Epoxy Sealer (CPES) sold by www.rotdoctor.com. It, as opposed to other sealers, is a epoxy that is manufactured from wood pulp. It's purpose is to fill the empty wood cells with epoxy so that their ability to absorb water is reduced. While the product is an epoxy, it does not cover the wood with a hard brittle surface, which in turns allows the wood to breathe. This concept is crucial to the life of a traditionally built wood boat as the water that does get absorbed by the wooden hull evaporates in the bilge and dry areas of the boat, thereby not allowing the wood to become water logged and there a host for rot spores. Wood with a moisture content above 28% will host rot spore. The product is also safe for interior use once the curing process is complete. Good luck with your project, it's pretty intensive.

[59toaster]

Originally posted by 62 Overlander
Having extensive experience with wood boats I can appreciate the desire to seal the wood floor. Especially after replacing a section under the front window in my Overlander. There is a product that I would highly recommend to seal any wood product. Clear Penetrating Epoxy Sealer (CPES) sold by www.rotdoctor.com. It, as opposed to other sealers, is a epoxy that is manufactured from wood pulp. It's purpose is to fill the empty wood cells with epoxy so that their ability to absorb water is reduced. While the product is an epoxy, it does not cover the wood with a hard brittle surface, which in turns allows the wood to breathe. This concept is crucial to the life of a traditionally built wood boat as the water that does get absorbed by the wooden hull evaporates in the bilge and dry areas of the boat, thereby not allowing the wood to become water logged and there a host for rot spores. Wood with a moisture content above 28% will host rot spore. The product is also safe for interior use once the curing process is complete. Good luck with your project, it's pretty intensive.

Thanks for the tip! I will look into that product
Want to make sure when my Kids end up inheriting this thing in 30-40 years it will be in better shape than it is when we inhertied it.
What do you think of my idea of covering the whole deck with Sheet flooring before dropping the body back on?
I hope to avoid having to pull the body but I plan to do this only once so I'm not cutting corners if I find any more than the two areas I know about I'll strip it to the gills and redo everything.

I also have some concerns about the insulation under the floor holding moisture and contributing to the problem. Anybody have any thoughts on how to do that different? I was thinking of using these foam peices that they use in houses where the insulation may come in contact with the underside of the roof. It provides a air space to alow moisture to have a place to go as it evaporates out of the wood. Should hold the fiberglass insulation about an inch off the underside of the deck. I think in this application I would cut some holes in it so the air can move in and out of it. In a housing application it's to alow unimpeded air flow from the sofits to the eves. The main goal is preventing direct contact between the wood and the insulation especialy if going down the road any water is driven into the cavity between the pan and floor.

[74Argosy24MH]

Years ago I worked for one of the SOB manufacturers. After the wood deck was installed vinyl flooring was installed edge to edge, the walls were installed over it. Probably a good idea for a SOB that has a life expectancy of 15 years or so. But there is a considerable amount of flex in the frame and floor, the flooring will begin to crack along the floor seams. If you are looking at 30 to 40 years the flooring will not make it.

John

[59toaster]

Originally posted by 74Argosy24MH
Years ago I worked for one of the SOB manufacturers. After the wood deck was installed vinyl flooring was installed edge to edge, the walls were installed over it. Probably a good idea for a SOB that has a life expectancy of 15 years or so. But there is a considerable amount of flex in the frame and floor, the flooring will begin to crack along the floor seams. If you are looking at 30 to 40 years the flooring will not make it.

John

Well the Stuff I'm looking at may work. I use to do comercial flooring so I know of some different stuff on the market. Your thinking about the paper backed flooring and yest in a trailer I think the flexing would get it. The wear coat is pretty thin on that stuff and the contant flex I think would eventually tear it .There is a pure vinyl flooring with no back and it has a good bit of streach to it. Time may ultimatly get it but I think I could expect a good 20-25 out of it in a camper. It took 15 to wear out some we had down in the house I grew up in. I'm also thinking of putting a pergo type wood floor over the top of it. That will elliminate the UV issues.

[Pahaska]

After the wood deck was installed vinyl flooring was installed edge to edge, the walls were installed over it. Probably a good idea for a SOB that has a life expectancy of 15 years or so.

The brand new International CCDs have vinyl flooring installed in exactly that manner. The vinyl is an option on the International AS, as well. Apparently, Airstream thinks it will hold up.

There is no belly pan. Under the wood floor is a black plastic barrier.

[Paul Mayeux]

If I were in the same position I would lay the vinyl down like in the new ones and then start up. I noticed on my Overlander that the Armstrong vinyl tile it came with was evidently laid prior to the shell going on as it was all under the channel that bolts to the plywood.

I also had a thought about the floor needing to breathe on an Airstream. If this were true, would the vinyl floors they put down now as well as the VCT they put in back in the old days not impede the transfer of moisture? That being the case, I personally, would not worry about covering the bottom side with insulation. But I would go with one of the rigid types like they use on roof decks under rubber or metal roofs as opposed to the batt type. There is a company called Bay Insulation Supply Co out of Green Bay, WI. They have an outlet in Atlanta at 404-355-5770. They sell any type of building insulation you could think of with your choice of backing. Anything from foil backed to polypropylene. They also handle the rigid board style. I know here in North Texas that you need all the insulation you can get.

[Pahaska]

In my old Scamp, the entire trailer was insulated with the foil-bubble-foil stuff that can be found at HD or Lowes. The insulation was covered with a fuzzy fabric. It was a very snug trailer.

After a week on the pavement at Cesar's Palace in Las Vegas at up to 115 degrees with the heat coming up through the floor, I decided to insulate the floor as well. I used the same foil-bubble-foil material. I sprayed it with 3M adhesive and stapled and/or nailed strips around the edges. It really worked well in our Texas heat.

[Paul Mayeux]

do they carry the foil bubble foil insulation in the isle with the batt insulation? I've never noticed it but I'd like to try some. How thick is it? I haven't riveted my interior skins back on and that may be a better way to go rather than piece the original stuff back in. Especially since some areas looked like they were just the scraps. Lots of little triangles and squares in some places.

[Pahaska]

It is at the rear of an aisle, adjacent to where the batt insulation is displayed in our HD. There are also rolls of foil and specialized insulation in that area. They have rolls sized to fit between 16" and 24" studs and also 4' wide rolls. I also found it at Furr's and in my favorite hardware store.

The insulation is about 1/4" thick. There is a plastic film under the foil on both sides, so it is quite strong. It does stretch nicely around curves like the interior of the Scamp.

I'm tempted to do the International the way I did the Scamp.