Starting at foundation not siding you can install pavers against your house foundation as long as it is the foundation itself.
Concrete patio against siding.
The siding should be 4 8 inches above the surface of the concrete.
I would advise locating a vinyl siding company and getting them to break some scraps that they ve laying around about an inch much higher than the concrete will be poured and as far out from the house as the scraps will go.
Typically when i pour concrete against a house foundation never pour concrete against any siding imho it invites trouble later i have an expansion joint set to the house.
Large roof overhangs can provide protection in some cases.
The best thing to do and it s the code in va is to put aluminum coil in between the wood and the concrete.
This means that you can lay the pavers against the concrete of your foundation as it rises from the earth.
Concrete absorbs and holds water and most siding and trim materials including fiber cement aren t rated for contact with concrete.
You are right to be concerned about placing the new concrete step in direct contact with the fiber cement trim or most siding and trim materials for that matter.
Observed non standard installation of concrete on the patio see photo this section.
Other times an l flashing over the surface of the concrete and work but keep in mind this can also trap moisture behind the the concrete.
It can be cork 1 2 thick by 4 tall set to the wall with short pins to hold it while pouring.
It is unknown what type of water insect access is available occurring under the siding below the surface level of the cement.