I've got an 18ft trailer that needs the floor replaced. I want to replace it with steel (it's wood), any of you fellas do this or have done it before that can lead me in the right direction as far as what type of material to use and maybe how much it might cost?

Most steel shops carry the grid material that are used in Car Wash grates. It was about $400 for the material for a 5' by 12' trailer.

I think it is called expanded metal. Price depends on how heavy of metal you use. You can also use tread plate. As high as metal prices have gone it could be more than you think to get it done. I would call a couple of places that make trailers and ask what to use and how much for them to do it for you. Make sure to ask what material they are using so you compare apples to apples.

True!! I did mine 6 years ago.

Thick expanded metal isnt cheap. Of course it depends upon what you'll be carrying on the trailer as to how thick, how many braces, etc. But being it is an 18 foot trailer, I would assume you'd want to roll some pretty heavy cargo on it...and that's going to cost you. If you have a welder, then go to directly to a metal dealer and save some money by doing it yourself.

the steel is expensive...found that out. I may just have to go with the wood.

can I use just regular treated wood or does it need to be something special?

Regular treated is fine if you are going cheap. Its what most trailers are.

Treated 2x12's or 10's aren't too cheap either, especially to do an 18 ft. trailer but they are stout and will last forever...Compared to the prices of metal they will be much more inexpensive...

thanks

Fud the new treatment in lumber will eat steel and fastners. Your best bet is to use Oak trailer flooring or go with untreated lumber but it will degrade quickly if left in the weather. If you don't mind the drive I will get you a number of a lumber supplier in Alto, Texas that can supply what you need in rough cut hardwood tomorrow. They can ship as well but it might make the cost way expensive.

pressure treated 2X6 is the way to go, may have to hunt to find 18' but that is what I would use.
spend the extra and get stainless bolts for it.

I'm not for sure on this, but if the trailer was painted, or at least primed beforehand you wouldnt have to worry about any corrossion...Also just use galvanized or stainless fasteners and they will handle the treated lumber..My brothers and I just replaced the floor on our cattle trailer last year...TReated 2x12's and some big galvanized self tappers and we were in business..Actually it was a big pain in the [censored] cause tappers that big require the right tools to be able to use them, We predrilled with an 1/8 bit just to aid in the screw getting started, even with a pneumatic impact it still was a battle but worth it once we were done..

I have replaced 3 trailers floors with treated and use galvanized bolts and nuts, I also spray mine every 2 yrs with sealer .