Decks, Patios, Porches and Docks - patio/stamping question

I have a 9'x12' patio (in good shape) and am exploring a few options.

I would like to know if it is feasible to expand the patio area DIY and then having a pro come in and "surface" the whole thing by stamping. i.e. can a pro "stamp" over an existing patio and does said patio need to be extremely high quality for the surfacing? or do you need to stamp when it is first poured? also, the expense of this vs. a pro doing the whole thing and would they have to bust out the existing patio?

I am in Indianapolis (Pecos), so we have decently extreme temperatures (I originally wanted to tile it).

I have already read some about making a base and so forth. I have no plans of enclosing it and am just getting started in my research. TIA

Luke

1)There are companies who do what are called stamped overlays. These are installed over already cured concrete. They consist of a thin (about 3/8 inch) polymer modified, colored cement/sand mixture which is then stamped in a pattern and texture. It's just my opinion, but I don't trust them much in exterior applications in our climate. However, these companies install a lot so they must be having some success. Just remember that the overlay is only as good as the concrete it is placed over. If the new slab heaves or settles, the overlay will crack and flake off at the joint where new meets old.
2)Traditional stamping is done in fresh concrete, so if you wanted that, your existing concrete would need to be removed first. I've been stamping (concrete, not overlays) here for the last 13 years with no problems.
3)As with anything, it is cheaper to DIY than to hire a pro, but can you do a high quality job? If not, you've got a cheap, bad job that will probably have to be replaced soon anyway.
4)You are wise to have given up on the exterior tile.

Pecos

I had a customer with a plain jane basement floor, and she had a guy come in, score along the walls about 6" in with apparently a masonry blade in a circular saw, then proceed to make a pattern all over her floor in the same manner, some diamonds, etc. Then he came back with a leather like stain in several colors and clear finish. This floor will take your breath away. It may be possible to do this on the exterior, may have to check around. It may be better than adding a surface to a questionable pad with an extension. That way if the two heaved, who would know it?

Yeah, I gave up on the tile pretty quick, once I actually started researching it, too bad.

I think it may be wiser to just extend the area with a deck, but as for overlaying the existing patio, are there many companies around us that do it? and why did you never get into overlaying? did you have a bad experience/problems with the process/results? how did you form that opinion for our area?

I am pretty confident I could do a good job, and as you know my soil is pretty much all clay after 4" of topsoil, will that help it not settling?

Also, how much would I save if I broke out the original concrete, dug out the new area and put in and compacted a 4" base and then had the pro come in and pour the whole thing and stamp it? probably about 250 sq ft total.

Luke,
there are several local companies that do overlays. I never got into it because I have seen a LOT of overlays fail (delaminate) here. It could be the companies doing the work, but there are so many that I doubt it's just the installer. I don't like overlays for the same reason as tile. They are two seperate layers, concrete and overlay. If water gets between them and freezes, the overlay pops off. I don't want the headaches of going back and re-doing work. With stamping, it's all monolithic. I've never had a top flake or peel off in 13 years. Also, we have plenty of stamping business so I don't need to venture into overlays. I've considered looking into them for winter (inside) work, but never for exterior applications.
The process Chandler referred to is acid staining, which we also do. It works outside, but looks better on a smooth slab which is typically on the interior. It can look good outside, but not usually on brushed concrete. A different method of texturing will yield better results.
You would probably save around $2.50 per square foot if you did all the tearout, hauling away, filling, and compacting yourself. That translates to about 1/4 to 1/3 of the cost of stamped concrete in this area. Good luck.

Pecos

Thanks guys!

I appreciate the helpful information.

Luke