My new to me 94 logan competetor has plain wood decking.

The angle iron cross braces are to far apart for the composite (plastic) decking.

As far as wood plank decking, the weak point is that it is a "single layer" of wood, in other words if there is a weak area of the wood grain, there are not other layers to make up for it as there is in plywood or Microlams (LVL)

I wanted to replace it with something like LVL lumber (this is the engineered lumber beams, typ 1-7/8" thick.)

If anyone has ever worked with LVL's they know how strong they are. But I can not find them in "exterior grade"

The thing I want to do when redecking is get away from the "single layer" decking, so if there is a hidden weakness in one board, I do not have a failer.

My next thought was to run new 2x8 PT #1 boards length wise (as the originals), then install a 2nd layer of 5/4x6 PT deck cross ways, then my rubber mats.  Any thoughts on this plan?

Thanks,

Nick 

Find a local sawmill that cuts hardwoods. A white oak board, eight quarter, (2" thick) by 10" or 12" wide, will be strong enough to support your horses without having to cross grain the surface. Allow a spacing between the boards with a 16 common nail, to allow proper drainage and allowing the wood to dry. Properly maintained, an untreated wood floor can last decades without rotting.

There are several species of hardwoods that would suffice. It all depends on what is locally available to you. If your trailer is aluminum framed, do not used treated boards against the aluminum.

I have a steel framed Logan GN 3 horse , the boards run UNDER the divider (dressing rm), So I am stuck with 1.5" boards.

I have 2 local mills, one is a larger operation that pressure treats.

I could have white oak cut then pressure treated?

Is the new pressure treatment ok with steal frame??

Thanks,

Nick 

Just put a membrane between the wood and metal so the Pressure Treating doesn't come in contact.

They make asphalt/Butyl membrane that comes in 6" of 9" widths that is designed to flash windows on new homes.  I would think that would be easy to apply and provide the protection you need between the boards and wood.

When using pressure treated materials with steel, you have to use galvanized or stainless fasteners. The treatment will eventually degrade any uncoated steel products. When the boards are removed for replacement, it presents an ideal opportunity to treat the steel frame structure for any possible rust issues.

Any surface rust can be removed, a conversion product like Ospho can be applied, and an undercoating using bed liner materials can be brush applied. The frame members can then be covered with a treated board without any physical surface contact.

The newer "Bed Armor" bed liner material by Dupilicolor, is one of the few companies that advertises this product as being compatible when applied over wood. I have used it many times on steel and aluminum but not on wood, so I can't relate any specific results. It has been unfailing in my other usages.

It would take some extra work with a hand electric planer, but the 2" boards could be thinned a half an inch just where they go under the bulkheads, and left at 2" for the stall areas. White oak is very strong, and unless you're transporting work horses, you shouldn't have any problem with the six quarter boards. If the mill will allow you to select your own boards, you should find some that are quarter or rift sawn which will be stronger than slab sawings. Eliminate those with shakes and unstable knots and you will be left with some decent lumber that will work well for flooring.

When the boards are placed side by side, be aware that they will shrink a bit over their widths, so any gaps will grow as the wood dries. A 12" rough cut, air cured board, can shrink as much as a half an inch in width. It's shrinkage over its length will be much less, depending upon its moisture content when its cut. Any hardware that is used in its installation should be allowed to move within the wood as the shrinkage takes place, other wise the wood can be crushed at the hardware point, or the hardware can bend. The easiest way is to slightly over size the holes in the wood.

Finding white oak aint gonna happen, much less custom cut and dried.(called local mills, they tried to sell red oak).

I have to slide the boards in from the tail end (under the rear tack and dressing rm walls, so 1.5" max.

Called local reputable trailer dealer, they said go to HD and use reg PT, they were clueless about CCA vs ACQ.

No way would I atempt to put green boards down, way to much shrinkage.

The larger mill does list CCA (they sell to excavators, marine), so I could get a pine, popular or other common specis in CCA.

My trailers cross bars (2"x2" 3/16 angle) are on 13" to 27" spacing, While the trailer decking is out, I am going to clean the frame and weld in additional cross angles. after adding the angles the widest space between cross angles will be 13".

I was thinking about laying in (and welding) expanded metal sheets, before putting the decking on,, but this would be a pain to weld in and paint.  I would put the expaned metal as a "fail safe" if a board gave way.

If I could just find some dried white pine :(

Nick

If you can get rough cut Poplar, use it instead of the White Pine. It's much stronger, harder and less resistant to rotting. We use it for horse carriage construction. Ash and the various Sugar Maples (hard or rock) are also strong woods that would suffice.

The soft maples and Red Oak are less desirable for exterior flooring construction than their cousins. They are commonly used for interior projects, such as mill work, cabinetry and furniture construction, where they hold up quite well.