That will depend on how you want your cleanups to work.
You could set the current elevation to 100 cm and activate the Replace Z Value with Current Elevation tool. That would put the baseline of the new Walls at +100 cm.
You could draw the new Walls with the baseline at 0 cm and then edit the Floor Line so that all vertices are 100 cm above the baseline.
You could duplicate your Wall Style and set the bottom of all components at 100 cm above the baseline.
David Koch
AutoCAD Architecture and Revit User
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