Currently its a grass /dirt mix where future patio is getting leveled/sloped set… small 12x12 stepping stones currently exist and are old/shabby gotta go type…about a 10 x 10 area… patio slab will be below houses entire south wall - current set up only takes up 1/3 of houses south wall… I have a crawlspace with generally good water/flood flow/control; I’m just worried if larger area of sloped concrete is better/worse overall … thanks for your professional opinion in advance of you comments. Tony
As long as you add exp joint to the existing wall and make sure the new concrete slopes at min 1/4 to a foot from the foundation you should be fine
its okay to place concrete up to walls as long as you allow 1/2 inch separation between the wall and new slab for expansion.