Bricks, Masonry, Asphalt and Concrete - cobble pavers - questions re: base

We're going to be installing a cobble paver system. It's actually 3/4" material, (nothing more than foot traffic), backed by mesh, so it's installed in sections. This product can either be installed in the typical paver fashion, or can be layed over concrete, set like tiles in adhesive. For both installations, there is a morter that is filled into the spaces, finishing off the "cobble" look. My questions are regarding the various areas and the base.

I'll try to describe the setup as best as possible, as I hope this makes it easier to understand the layout. We have a walkway along the front of the house, a breezeway that connects to this walkway, and then also connects to a concrete patio off the back of the house. The concrete walkway and breezeway are in good condition, so I'm planning on installing the pavers directly over this concrete, using the manufacturers specs. The concrete patio has a couple cracks, so I'm thinking this should be ripped out and replaced. Also, we're going to expand the surface area of the cobble pation beyond the concrete patio, so that's another reason why I felt it should be ripped out. Now, should I plan on having a new slab poured for the patio area, or should I do the various layers of stone, sand, etc? Which is the better value? I figure it may be cheaper to do stone/sand, but won't I have greater stability with the concrete?

Any thoughts would be a great help.

Thanks,
Dan

I'm no expert, but I don't know that I'd take the trouble to demolish the cracked slab unless it's in really bad shape or the ground is heaving it. As they say, there are two kinds of concrete: concrete that has cracked, and concrete that is going to crack. You have the former, and installing new concrete will just get you the latter and will delay your installation while you wait for the new concrete to cure.

As for the new expansion, I think I might go for the stone and sand bed.

Upon doing some more reading, I understand what you're saying about the concrete cracking. I'll look at it more closely to make sure we don't have any heaving or height differences.

Since I am planning on expanding this patio area, I guess my only remaining question is this - For this patio, if a portion is cement slab base and a portion is stone/sand, will I this cause any problems over time. To again give the best image possible, the patio is currently a bullet shape, about 20 x 10. Without having an exact shape and measurements, we are looking to roughly double this size.

A 3/4" paver is not a real paver. It is just a thin veneer that is attached to a solid base. You are apparently considering a facing for a concrete surface.

A real paver is a solid unit that is a part of a system including the base. The use of this system ranges from walkways to airport runways, depending on the base. Normally, they are laid on a gravel base, for maximum capacity and economy. Sometimes they are laid on a concrete slab for decorative uses.

You cannot combine the two applications because of the difference in base properties.

The meager grout joints will crack if they are expected to span between a concrete base and a compacted soil base.

If you want a "pretty" small surface and not a larger heavier capacity area like a driveway or street and want to use thin surface veneers over an existing slab, then a veneer will work. Please be advised that you can expect any cracks in the concrete to be telegraphed through the "paver" joints just as they would be in a tile floor.

Dick