flooring help - moisture proof or jack up floor?
 

I need to install new flooring. I have an uninsulated craw / walk space.

To install wood flooring I am told that I would need to moisture proof. For assorted reason, I cannot lay moisture barrier on the ground. Could it be attached to the underside of the floor? How and what would I attach?

The other option is to install tile. To do this I will need to increase my floor strength with joist supports.

I'm not sure which is the best option.

I guess I could allways go with vinyl tiles. But I'm not convinced that vinyl tiles in the living room would look acceptable?

I do not want carpet.

Every option seems to have multiple complications and my brain is getting frizzled trying to decide which way to go.

Any expert advice would be greatly appreciated.

Since no one here knows why you can not install a vaper barrer on at least the crawl space area, no mention of floor joist spans or widths.
We also need to know what you have now for a subfloor and underlayment if there is any. Need thickness and what material it is.

Joe:

I do not know what the joist's are made of. The house is 40-50 years old.
The joists are 7 1/2 inches by 1 1/2 inch.
The joist spacing is on 16 inch centers.
I think.... that the span is about 11 to 11 1/2 feet.
It looks as if my subfloor is one sheet of 3/4 plywood.

I am going to look it over soon and see how much of a pain it would be to shorten up the joist spans. I plan to add subfloor.

The reason that I cannot put moisture barriers in is because this house is built up over a crawl space / walk in area that is subject to occasional flooding. The house is high and dry, but it occasionally gets inundated below.

I'm guessing that wood flooring would be a crapshoot (although the neighbor has had wood flooring in his house forever with no issues) But it's too pricy to gamble with.

I don't think there should be any need for more support with you joist spans 3/4" will be strong enough if in good condition to do hard wood right over.
If you do tile you will want to add a 1/2 ontop of the 3/4" ply or backer board.

I think your basement hight is good enough for any floor really but that's my thoughts.