Thanks for the information everyone. I didn't build the shop, so I'm not quite sure what is under the slab, but I do know it is about 12" thick and reasonably sure there is gravel under it. No floor drains, all above ground. One side has a pole barn attached to it so it's basically protected from the weather. (not even going to attempt to dry out the barn)
The insulation is just a thin/spotty layer of blown in fiberglass on the attic floor.
I have a giant exhaust fan on the roof, which pulls air from the shop through the attic man hole. I could leave that running, but this being Oregon...the humidity outside is often just as high. I really just want to seal the whole thing up so that after the dehumidifer does it's job, it will stay sealed and dry. As it is now the humidity starts climbing the second I turn off the dehumidifier. (which is an old 5,000 BTU air conditioner) I am absolutely amazed how much water it can pull out of the air...and I don't understand how it comes back so quickly!
One thing I'm thinking about is the block walls were built, then the floor was poured inside. The floor has shrunk maybe 1/16" all around the edges, maybe I should seal up that gap?
I do have some "stuff" bubbling through the paint in one small area, but it's dry and chalky, not wet at all.
I do want to repaint the inside white...is there any special type of paint I should use? I know they make sealers for basement walls and stuff, but I think you have to put that on before any paint...
