Vinyl over decking in basement

[Robert Venable]

Ok, previous owner laid decking in basement as floor, no moisture barrier below it, he used it as a workshop. Can I install vinyl floor over the decking? Maybe if I put 3/4" plywood down first?

Should I lay moisture barrier on the decking, then plywood, then vinyl floor?

Things to consider: There is not currently heating or air into that room, but there will be someday soon. That, to say, there really isn't any humidity concerns at this point, but if it rains for a week straight, it gets a little muggy (hopefully that will change once I get the room finished with heating/cooling).

 

[Floorist]

I have seen mixed results with vapor barriers. Sometimes it stops mold and sometimes mold grows under it. You really need to test the concrete with a moisture meter.

 

[highup]

If that is below grade, and you install vinyl, the vinyl will get wet on the underside. Moisture constantly evaporates off the concrete so often, you never know moisture is present.
Installing the vinyl will prevent the moisture from evaporating... It will just build up under the vinyl. Heating that area will only make it worse.
Like Rusty said, have the concrete tested for moisture because otherwise you will never know if moisture will be an issue.