You could build you shed right on top of the concrete slab, just like they do with a house on a slab. You didn't say want you wanted to use this shed for but you might want to consider "the lay of the land". Sometimes when slabs are poured for sheds they aren't quit as high above grade as they should be. You don't want to find that the floor of your sheds ends up under water after a heavy rain. To connect the base plate of the wall to the concrete youÂd need to use an expansion type anchor. There are a couple of variations  a wedge type and a sleeve type but they all do the same thing  expand in the hole to make a secure connection to the concrete. Generally speaking things like powder actuated fasteners and "Tapcon" type screws arenÂt sufficient. A hammer drill makes drilling holes in concrete much easier. You can rent one for $20 or so. Any wood that comes in contact with the concrete must be pressure treated. IÂd also run a heavy bead of construction adhesive under the wall base plate to form a seal. A "jack hammer" is generally used for destruction, not construction. You didnÂt mention anything about permits. Many communities require permits for this kind of construction and you local building department can be a useful resource if youÂre less than sure of your carpentry skills. Certainly the inspector isnÂt going to help you drive nails but he can make sure you donÂt get into too much trouble. Good luck! Mike

Thanks EATREALFOOD. Dh didn't say much when I told him. oldbat2be, your floor looks perfect. Mine is concrete slab which seems to make a difference. Christine, I've been doing internet searches and find pretty much the same answer everywhere, even eHow, that you can't lay a tile across that joint, there has to be a grout line over it filled with a special caulk, not grout. Called a soft joint. The other part we are puzzling over right now is using a flexible membrane under it. I was going to use Ditra, but was told that it wasn't made for this. There are some paint on membranes, and there are some mesh membranes. And people who use the paint on type seem to do the whole room with it. I also just saw a youtube video that says the industry standard requires a soft joint every 10 feet in a large room, or even a shower wall to prevent cracking when the house shifts. I didn't know that. Maybe that's why we had some cracks in our first tile floor. Also, our floor isn't completely flat and the pros seem to be divided on how much is acceptable. We either have a huge low spot that is 1/8" lower than either side, or we have two high spots that are 1/8" higher. And is a 1/4" high spot enough that we have to go get another super grinder, or can you adjust it with thinset? That's the big issue we're trying to solve right now.

The post above carlos229 is not the OP. One thing I was going to point out about the difference in cost: If you divide the total cost by the proposed # of piers, you get $1600/pier for one contractor and $1700 for the other. So their rate per pier is not far off at all. I did the same thing with foam jacking my sinking driveway. Had estimates from $980 all the way to $2200. Each estimated an amount of foam plus a per-pound price if they went over. I calculated the cost if everyone used the same amount as the highest estimate, and the estimates came out within a couple hundred bucks of each other at that point. So I picked the guy I liked best. He wasn't the cheapest one but it didn't make that much difference. Question is how many piers you need, and I can't help with that. I liked the idea of hiring someone who has no stake in the game to tell you want you need.

I am about 150 miles south and just pulled out all tile and carpet replacing with new tile throughout except 4 bedrooms. i entertained the idea of polished concrete... love the look. But decided on tile and glad I did. Once everything was pulled up, found surprises. Cracks, funky chipped away part in three spots, and at some point some portion had linoleum or something (black glue gunk all over). Plus, if house is built right you should have expansion openings (the are called something fancier). If/when you tear out tile, be sure you have a budget to replace if needed.