I have Mannington Adura tile for our basement bathroom. Our concrete is pretty level, no cracks, there is a slight dip back by the toilet that I am going to fill in with self leveling mix the toilet will cover up but thought I should fill in to keep the tile level.
The bathroom is small 5ftwide by 8ft long. These tile are glue down and then you can grout or but tiles up next to each other(probably will grout). I am wondering if I should lay any type of sub floor down or just go right to the concrete. The Store said just go right to the concrete but don't always trust that opinion. Any tips?
Adura is a luxury vinyl tile, not a ceramic. According to Mannington's installation instructions HERE (pdf) you can install it directly to the concrete.
With products such as this you want to thoroughly read the instructions and follow them to the letter. You must use their grout for it which is an acrylic-based pre-mixed grout. I know nothing about this particular product but I have found that, in general, any pre-mixed substance has a tendency to re-emulsify if subjected to significant amounts of water. (It'll turn back into goo. ) I don't know if that product does or not - I've never used it.
Mannington seems to have a specific underlayment for this product which is a sheet membrane. If you want an underlayment you may want to contact them and ask about it. I wouldn't use anything they don't specify. If you do I'm fairly certain they wouldn't warranty the product due to the installation method.