I had a pool installed a few years ago and the builder threw in a narrow concrete patio around it. See fuzzy picture below (sorry about that. Google earth must be a little tipsy tonight).
So now that I've paid off the pool, I'm thinking of putting down a flagstone patio, but the trick is that I want to extend it beyond the paltry concrete patio that already exists (dotted square around pool).
I assume it will be a pretty easy job to lay down the stone on top of a nice level concrete patio, but I am a little concerned about how to make the transition between the concrete part and the grass part.
(1) Is this even advisable, or should I just extend the concrete out to the entire area I want for the patio before laying stone (adding considerable cost)?
(2) Assuming I don't extend the concrete, what should I do when the stone transitions from the concrete subsurface to the dirt? I'm nervous that cracks will occur over time, and I'd like to do whatever I can to avoid that.
Best Answer
Rolls-Royce job (Money no object): Extend the concrete slab out to the area you wish to pave or remove the existing slab and start allover again.
Good enough job (and what most paving pro's would do, at least the ones I know back in the UK): Excavate 6 to 8 inches (150 to 200mm) from the area you want to extend into. Back fill that area with sub-base (crushed rock) material. Back fill in 2 to 3 inch (50 to 75mm) layers, each layer should be "properly" compacted. This will give you a sub-base that is "nearly" as good/stable as the existing concrete slab.