Trailer Wood Deck, Treatment?

I just bought a new 32ft GN flatbed with pressure treated decking and want to seal the deck before the sun eats it alive.

What I'm thinking of doing is taking each plank off then sealing them on all sides with pick-up bed coating. I would lightly (thin) seal the sides, ends and bottom then reinstall the deck then heavy coat the loading surface just like a pick-up bed gets coated.

I'm thinking it will seal in the existing moisture before the sun can decompose the wood.

Anyone see why I shouldn't do this? Or have a better idea?

T_Bone

I was wondering if the sealant would seperate from the pressure treated wood or even stick to it and since that was confirmed, it's on to plan "B".

I asked the mfg what to put on and he said they all use 50/50 motor oil/diesel with a sprayer. So I think I'll give that a try although it goes against what I've read for taking care of gun stocks. They say that since motor oil or petroleum products are decomposed oils, applying them to fine wood will accellerate wood decomposition but using new vegetable oil will not.

Then I'll lay on a 14ga steel deck, skip welded on the edges and seams, shoot a couple center screws, then paint with anti-slip floor paint.

I already see a 3/8" gap in one of the joints and it's only 2weeks old with tight joints when I picked up trailer. At 104º and 15%rh it's going to shrink fast. I bet I see some splits show up shortly.

T_Bone

It took about 4 gallons to do the 8 x 16 deck. I really let it soak in and fill all the cracks and checks in the wood. Although boiled linseed oil is much more expensive than I expected it to be, it is lots cheaper than many other treatments.

When I installed the new decking, I found that it was very hard to get the pressure treated lumber to slide into the slots the old plain lumber had been in. It took some heavy persuasion with a sledge and in a few cases, a bit of rasp work to get the planks to go in. I don't know how your decking is installed, but adding to the thickness of my decking would have made the problem worse.

I hope to build another pole building in the next couple of years, and then the trailer will be inside, which is probably the best storage solution, although certainly not the cheapest.

I don't know how you can deal with Arizona heat! I have been to the Phoenix area a couple of times in the Summer and really thought I would melt away.... Glad to get back to the naturally air conditioned Northwest, where it seldom breaks 100 degrees more than a couple of times a Summer. Arizona is nice in the Winter though. Good luck!

Could sure use some of that Arizona heat to cure a couple of hay fields about now.

BUT... I may never get the chance to answer a question from the wisest man on the internet, so here goes nothing!

I tried using truck bed liner spray to paint a couple ramp boards (to load a lawn tractor in a pick-up bed) a few summers back. Long story short, first time the boards flexed, it flaked off. It just didn't bond to the treated wood like I thought it would.

Also, my wood trailer deck gets hammered. Loading every sort of old farm equipment. Cultivators, plows, disc's, ect... rip the wood to pieces in a couple years. No need to worry about long-term preservation on mine....

I do what someone already mentioned. Used motor oil mixed with some diesel fuel (About 70/30% mix) I paint it on with a paint roller 2 or 3 times a year. (Don't do it on a hot, sunny day....) Best done when cool or cold.

One problem I see with waterseal products would be making the deck slick when wet. (Suprisingly, the oil/diesel doesn't do that... It absorbs into the wood, and to some degree, raises the grain on the wood, making it more NON-SKID, than slick)

I don't know how well it will work with treated lumber but I have made the wood floor of a 1967 Ford F600 last (and look good) by coating it with old motor oil two times a year. Much like the oil deck stain/finish you can buy it soaks into the wood and keeps a decent moister content while repelling water. It cheap, easy and efficient.

I don't think what you have in mind will work. First of all, trying to maintain the existing moisture in a new pressure treated deck is a losing proposition. The moisture content of newly created pressure treated wood is several times higher than the natural moisture content of the green wood it is made of. I believe no matter what you do, that moisture content will continue to drop. And the wood will continue to shrink until equilibrium with it's environment is reached.

So as I see it, if you were to apply pickup bed coating while the moisture content is high, not only would you have a hard time getting it to adhere to high moisture content wood, you would soon find that the hardened bed liner material would be, in essence, bigger than the wood surface it is applied to and it will come loose.

Although there is a certain amount of common sense in the idea of retaining wood moisture, in a climate as hot and arid as yours, it just isn't practical. I know this is true of furniture making. If I made you a piece of furniture here in east Texas, where the summer humidity is very high, no matter how well I finished it, it would soon develop cracks and space between joints, just sitting in your living room.

Personally, if I were going to go to the amount of effort you are talking about, here's what I'd do. I would monitor the moisture content of the deck with a moisture meter. I would leave it be until the moisture content stopped falling. Then I would take up the planks and paint on a coat or two of Smith&Co. Clear Penetrating Epoxy Sealer (CPES). I'd soak the ends by standing the planks in a coffee can of sealer for a few minutes. I would follow this with an oil based (non-polyurethane) floor enamel with the highest UV rating I could find. As you undoubtedly know, protection from UV is the primary goal in your part of the country.

I would let this age and weather for awhile. Then if you wanted to apply bedliner material on the load surface, you might actually stand a chance of it sticking and lasting for a good long time. In my opinion, the best part of your bedliner idea is the excellent UV protection you would achieve.

Again, I want to thank you for your input on so many topics, I'm always interested to hear what you have to say. I hope my opinions are of some use to you.

Michael

I had a pressure treated deck on a trailer and I
just bought some sealer from Home Depot that was
compatable and coated it twice a year. Trailer sat
out in sun, rain, snow, all types and looked like
new when I sold it 7 years later. I now have a
trailer with rough sawn hemlock and it is a pain
to try and keep from cracking and weathering. I
know when you buy something new there is a desire
to keep it that way, but taking off the deck is
a huge job. Most decks now are put down with self=
tapping fasteners that are countersunk so you may
end up ripping up wood backing them out and making
a new problem to deal with. Take the easy way and
buy the sealer and a sprayer and shoot it from top
and bottom a few times per year.

The main thing you want to do is to seal the end grain. Uneven drying of the wood is what causes it to "check" (split).

There's nothing you can put on that will completely stop the wood from drying. However, there is a product called "Seasonite" made by Flood. It is a glycol-based wood treament intended for new pressure-treated wood. It retards the drying so the wood doesn't check so bad. Worked well on my house deck: eight years later there's still no splits.

You could treat it just like a patio deck and get some of the good water seal stuff. It might just last a while. It will look better longer and clean up easier too.

When you're done, you could park it next to the house, add a table and a couple of loungers and be the coolest cat. 8-)

Regards.