As a previous commentor pointed out, make sure you use pressure treated for the sole plate. I would recommend getting a ramset to drive the nails into the concrete floor. In fact, I recommend buying one, you can buy a hammer activated one for about $18 at the depot and they're invaluable for fastening lumber to the walls when you want to add shelving. If you don't want to buy one, you can rent them from your local tool rental outlet for a couple dollars a day, but you'll still have to buy the nails and charges.