On Sat, 23 Apr 2016 21:02:44 -0400, Keith Nuttle
wrote:

On 4/23/2016 6:01 PM, Fredd Wright wrote:
I have a crawlspace in the basement that has a dirt floor right now.
I'd like to lay some sheets of 4x8 plywood (or other material) on it
to make a surface suitable for crawling on or putting things on. It
will lay right on top of dirt. It doesn't have to look good as it's in a
crawlspace in an unfinished basement. I't won't be exposed to rain but
there will be some moisture coming up through the dirt. Also, i'm probably
going to hose it off occasionally. In addition, every 5 years or so it
will be
underwater for a day or two when we get a hurricane as they usually
flood the
basement. Can anyone recommend something that will last but not cost me
an arm
and a leg? Again, i don't care how it looks.

While it has been mentioned in passing, I think the strongest negative
for putting wood, any wood product, on the ground in the crawl space is
the attractiveness to bugs, particularly termites. In fact if you do
put wood down there it may void your currently have a termite contract.
(Read the fine print)

I was under a house a couple of weeks ago, that someone had actually
poured an area of concrete under the house to provide an area exactly
what you area for exactly what you are talking about.

Properly prepared, a slab of 2 to 3" thick would seem to me to be
sufficient for a storage area under the house. You would not driving
cars on it and you will not be storing any heavy equipment.
Or level the area and lay a sheet of rigid foam insulation on the
ground, and PT plywood on top of that. Stake it down with 10 inch
spikes driven into the ground so it doesn't float away in the next
flood.