OSB as Flooring

[53flyingcloud]

Originally Posted by markdoane

Really cool site. Here's a new contest: Develop a 'usable' panel that costs less than $700 per 4x8 sheet, using the tools on that site.
(Note: their panels are 4' x 38', so it might work best for Airstreams less than 22' overall)

Companies such as this make it possible for products to perform at their best~!
Imagine if you will, an Airstream made with a "flooring" sandwiched with aluminum (of which, the thickness is your choice) on the top and bottom.
Additionally, it could be made with just two pieces of flooring material instead of 6 or 8 separate pieces bolted side-by-side.
The core of which, can be further designed to be either solid or honeycombed. Wet floor problems by-products are gone forever. No more holes in the floor due to rot, etc.
Why, you could even gain additional benefits such as, added insulation from the cold during the winter. (To name just one~!!)
Personally,
If I were to plan a shell off frame restorations, I'd seriously consider this option!
Dare we to think out side of the box???
ciao
53FC

[IceKing02]

Sorry about the wrong link. Here's the one you'll really want:

http://www.hexcelcomposites.com/Mark...ls/default.htm

You can see that there are PLENTY of prefabricated laminate panels. No need to reinvent the wheel, especially with the selections for heavy traffic areas. 53Cloud, they already make aluminum-faced laminates for cargo holds in a variety of strengths and with differing impact resistances. Just a matter of dropping it in and getting on with it.
As for the design of a 4' x 8' carbon laminate board for less than $700 it is do-able. Here are some of the links that might be helpful: www.carb.com/carbon.html for high-end carbon fabrics and www.generalplastics.com for 6700 series foam boards. The cost is in the labor and layup of the board. You'll need at least four layers of carbon fabric (on each side) for multidirectional strength. Its gonna be work!

Now about that OSB flooring...

[vajeep]

The big questions in my mind for anyone reading this post are:

Would you (or did you) use OSB instead of plywood?
Why or why not?
Would you treat it with any thing additional (expoxy, thompsons, etc.)

Osb (oriented strand board) = wood chips glued together
Sadly many builders have convinced their customers and even themselves that this product is equal to plywood. What the builder or Airstream does is to use a cheaper product and pocket the savings while keeping your cost the same.
I will not argue with any one about osb v plywood. It is too much a personal thing like ford/chevy gas/diesel ginger/mary-anne etc.....

But, just do a personal test and put equal sizes of plywood and osb out side for what ever time period you chose. As water comes in contact with each you will be able to see for your self.
my .02.

Abe
Ps my builder was forced to use plywood on my addition against his will. He had specified "plywood" in his contract that we had agreed on, and imagine his suprise when I refused to let him use osb on my addition. Any insurance adjusters might also see this. Storm damage contractors always use osb on the structure and bill the insurance company for plywood.

[Over59]

That link sure has lots of info. Makes me think my daddy was right when he wanted me to be an engineer, but I didn't like the smoke and noise.
I think I'll stick with the CPES and marine paint and sell the AS within the next 40 years.

[TomW]

Originally Posted by vajeep

The big questions in my mind for anyone reading this post are:
Would you (or did you) use OSB instead of plywood?
Why or why not?
Would you treat it with any thing additional (expoxy, thompsons, etc.)

...But, just do a personal test and put equal sizes of plywood and OSB out side for what ever time period you choose...

Ya know, I was going to stay out of this one: Too much of a Ford vs. Chevy thing. But I decided to treat this more of a poll, and cast my ballot.

I used OSB in replacing the aft, 4X8 section of rotted bathroom floor in my Overlander because I have unintentionally done the 'personal test' outlined above & studied the results. Although exterior grade plywood is assembled with waterproof glue, OSB wood chips are soaked in it thereby giving the final product more protection inside & out.

I debated treating all of the OSB with an additional product, but decided the edges were the only thing that would benefit (I have yet to see a rotted out hole in the middle of the floor). So, for water resistance, and as a slick surface to aid installation, I wrapped all the corners with duct tape.

Oh, and there are two Chevys & one GMC in my driveway

Tom

[Over59]

Here is an interesting product, plymetal http://www.jfreeman.com/metal_sheeting.html#flat
What ever I use I will coat with epoxy. The edges for water the rest to cut down on mold / mildew getting into the wood. I really am leaning toward a deck style marine epoxy finish on the floor with area rugs as needed for the canines. This plymetal with the aluminum side down would allow filling the pan with foam insulation, no? Price isn't bad and close enough I can go get it.

[87MH]

Originally Posted by psychpw

....What ever I use I will coat with epoxy.

Given the amount of flex the floors see in normal trailer useage - does anyone have any thoughts (or experience) concerning the epoxy developing cracks and flaking off?

[Over59]

Cracks Better do a test sheet. I'll let you know in a couple weeks.

[markdoane]

Paul,
Can you do one test with cloth matting and one without? And one with polyester resin? And different amounts of hardener? How about West Marine vs System 3?
Please report results and confidence levels. Please randomize variables.

[Over59]

Actually, blind examineers would be fine. Do you think the matting would matter? I wasn't going to use any. There must be a reason that this is not a common approach on the forum. Where's Andy the Wise?

[TomW]

Originally Posted by markdoane

Paul,
Can you do one test with cloth matting and one without? And one with polyester resin? And different amounts of hardener? How about West Marine vs System 3?
Please report results and confidence levels. Please randomize variables.

Paul - Please cc: me with the results

Don - Now THAT was funny!

Originally Posted by psychpw

Actually, blind examineers would be fine. Do you think the matting would matter? I wasn't going to use any. There must be a reason that this is not a common approach on the forum. Where's Andy the Wise?

No need for matting; This is for water resistance, not strength. Plus, matting would soak up more resin thereby adding more weight. For some reason, I doubt Andy's place uses much, if any, resin. Hopefully he will catch this post & respond accordingly.

Tom

[Tripp]

If you are going to seal the plywood with epoxy without fiberglass mat, flex will not be a problem. The thin viscocity epoxies penetrate into the wood and essentially become part of the wood as opposed to being a topcote only. The fiberglass mat should be used sparingly from a weight perspective. I plan on using a 6" tape to go around the perimeter of the floor with the tape wrapped around the edge of the ply so I have a 2.3" strip on the top and the bottom while the end grain is completely covered. I am also considering using a 2'x2' mat in the doorway to help as well. There shouldn't be any issues with this type of setup.

I don't think it would be necessary or advisable to completely fiberglass the floor (although it can be done). Weight is the major factor. My wooden canoes are very flexible and can take tremendous abuse without cracking. I have an uncompleted one without seats, thwarts, etc that you can twist and turn with no damage to the epoxy/fiberglass. I was using lightweight 4 and 6oz cloth.

I really like the composite idea. I had already planned on using the honeycomb composite for use as a substrate on the cabinet tops with thin 1/8" corian. I have my dad researching it further. He works for a major airplane outfitter.

My .02c

Tripp

[malconium]

How about the overall cost of the new floor with the various approaches?

I would like to use something that would be a permanent solution but I am certainly not willing to pay an astronomical amount to do it. Here are rough cost estimates that I have looked at so-far for a full replace of my floor. I would need 7 - 4'x8' sheets to fully cover my 31' AS.

1.) Preasure treated plywood (the non-toxic variety).
CCX plug and touch sanded about $69 per sheet (7*69 = $483)
CDX about $50 per sheet (7*50 = $350)

2.) 11/16" tounge and groove OSB sub-floor
about $29 per sheet (Lowes) (7*29 = $203)

How much for enough epoxy to coat about 200 square feet of plywood on both sides? I estimated that I would need about 2 gallons of Rot Doctor at about $150.

What kind of numbers are you guys seeing for your various approaches?

Malcolm

[Over59]

Thats about what I figure except I should be able to use the original 1959 plywood floor with minor patching. I'll soak it with CPES and then an epoxy primer and epoxy urethane top coat, then strip the walls. Let the expoxy protect the floor. Looking at about 250 total I would think for the floor stuff. If I have to replace the floor price goes up as I really like the plymetal concept. Everything is out but the tub.

[TomW]

I have yet to understand why everyone wants to use pressure treated plywood for an interior floor. Maybe where you live it lays flat, but everything I have seen around here is a warped, rough mess. And I would NEVER put any sealing coats on anything pressure treated unless it was allowed to dry for a year or two. Sealing in all that moisture is the kiss of death for wood products in spite of what ever chemicals it has been subjected to.

And, maybe your Airstream's original floor was a moldy mess that should have been treated at the factory for moisture resistance. Mine was not. I felt no need to apply "just in case" coatings to the original decking because it survived 37 years without my help. With the exception noted in my above post, I did nothing to the new decking I installed.

Maybe I am deluding myself, but with my new-found appreciation for how important it is to keep the seams etc. on the outside sealed against water intrusion, I would like to think that I will maintain my Overlander, AND know where the trouble spots are, in such a way that soft decking will not be an issue while I am enjoying its use.

I would say more, but I need to take my medication now...

Tom

[malconium]

Tom,

Actually I seem to be about the only one suggesting preasure treated as an option. If I were to use preasure treated I would not intend to coat it with anything (other than the floor covering of course). The hope being that the preasure treating materials do a good enough job and save me the trouble of coating with anything else.

It seems to me that most of the people that have commented on their approach in the forums favor some form of un-treated exterior grade plywood that is then treated with some sort of sealer. The two contenders that I have seen most in the forums appears to be epoxy or in one or two cases Thompsons Water Seal.

So far I don't remember having had anyone say that they would whole heartedly endorse using OSB even though it appears that the AS factory may be using it.

Most everyone seems to like the idea of having a material that would never have a problem with rot. The entry level costs for some of the more exotic solutions seem to be a bit too pricy still.

I am definitely intending to take various steps to help ensure that water is not a problem in the future (during the time that I own my AS anyway). This being the case you may be right that totally un-treated plywood might very well be just fine. I still feel a little uncomfortable with not having anything protecting the wood though.

The most vulnerable part in my mind is what happens around the edges since the body is held on largely by the connections from the u-channel to the edge of the plywood (or not held on in some places on my unit). At the very least I think that I will be adopting an approach that at least protects the edges. I am still pretty likely to take an approach that I documented elsewhere in these forums. I am actually looking at TREX deck lumber with the thought of making an edge band all the way around that is rot proof. That is one of the reasons that I thought OSB might make a good floor - use if for everything except around the edges.

I need to make a decision pretty soon - maybe over the weekend. I need to get the work done and proceed with other aspects.

Malcolm

[Ken J]

Tom

You raise some good points - I've often wondered if sealing with epoxy is really needed - when you put screws/bolts through it, seems like you would defeat the purpose of the epoxy............... Having said that, I've used eposy on my edges - figure it can't hurt.

Ken

[TomW]

Originally Posted by malconium

Tom,
Actually I seem to be about the only one suggesting preasure treated as an option.

In this thread, "Yes". I foraged through a multitude of threads when I was contemplating my floor repairs that suggested pressure treated lumber. If nothing else, bear in mind that pressure treated lumber was created more to keep bugs from destroying your wood as opposed to rot.

So far I don't remember having had anyone say that they would whole heartedly endorse using OSB even though it appears that the AS factory may be using it.

Earlier in this thread, I allowed that I used it in my floor repair. To me that was an endorsement. I try not to tell people what to do, only present case examples. If you prefer more sentiment, I whole heartedly endorse the use of OSB.

I still feel a little uncomfortable with not having anything protecting the wood though.

No problem with that. You need to do what you are comfortable with.

I need to make a decision pretty soon - maybe over the weekend. I need to get the work done and proceed with other aspects.

I fully understand schedules. Normally, I would say PM or call me if you think I could help you decide your course of action. But I am leaving at 0800 in the morning to return Sunday afternoon. Please drop me a PM if you think I can help.

Tom

[vajeep]

[QUOTE=malconium]Tom,
So far I don't remember having had anyone say that they would whole heartedly endorse using OSB even though it appears that the AS factory may be using it.

Does it bother any one but me that Airstream is using a "product" that (leaving personal feelings aside) That costs less than plywood and when exposed to moisture falls apart. I havent noticed a price rebate to the end user that reflects the cost savings. If in fact Airstream is the best of the best maybe they could use the best materials from the start. If some one could tell me how many sheets are in each length I will go to my neighborhood lumber yard and figure the cost diffeence per sheet. They still load your lumber for you, tie it up and put the red flag on for you..... Some days I just stop in so they will say my name. If any one is ever near Richmond Va stop in and visit a world class family owned business. Only open M-F till 4:30 but call if you are running late and they will wait.....(no kidding)
http://siewers.com

Abe

[TomW]

Originally Posted by vajeep

Does it bother any one but me that Airstream is using a "product" that (leaving personal feelings aside) costs less than plywood and when exposed to moisture falls apart.

I believe you are confusing OSB with particle board.