The first PCB I ordered here was one-sided and created with Fritzing and it turned out great.
For my next one, I’m using KiCAD and it will be double-sided. Are through-holes plated automatically when there’s a trace going to both the bottom at the top of a hole and for vias? Or would I need to solder both the top and the bottom of the lead going through the hole?
Also, does the plating reduce the size of the hole? In other words, should I make the holes a bit bigger if there’s a trace going to both sizes of it? If so by how much?