Question
We have a 12-year old existing concrete paver patio that was not pitched properly for drainage and gets shallow puddled water in areas. It  does drain away, though (contractor was a nightmare).   Consequently, sediment in puddles causes staining, plus a lot of moss, etc. in between pavers.  Would this all have to be ripped up or could flagstone be cemented over patio (assuming a better drainage pitch could also be done at same time?).  Perhaps a cement base troweled over? Or is it easier to pull up pavers (BIG patio). *Sigh*  Signed, "On a budget in central New Jersey"!

Answer
I am  alittle confused you say a concrete patio but then you say water puddles betwen pavers?
Do you have a concrete patio with Pavers over top?
Well assuming you remove the pavers first you could cement stone to the patio and make up for any low spots with the mortar between the stone and concrete. You could also trowel mortar or topping/patching cement over the base if that is the problem. Or if there is a sand setting bed between the pavers and the concrete you may just need to add sand in the low areas.

good luck

Sean J. Murphy, LA, ISA, LEED AP
Landscape Architect
www.seanjmurphy.com