I read the following post that concrete should not be against wood siding: http://www.thisoldhouse.com/toh/asktoh/question/0,,455294,00.html
Is it okay to have it against vinyl siding? I am guessing it isn't because moisture would still rot the wood sheathing and framing under the siding.
As a solution, I am thinking of pouring a concrete patio and leaving a 1 foot trench filled with gravel against the foundation, leaving 3 inches below the siding. There is a ~24 inch overhanging roof, and I plan to have the patio slope away from the house. I am hoping this is sufficient to keep moisture away from the trench. Is it overkill to add a french drain to the trench? Anyone have any other suggestions?