I want to make myself custom wood entry door. What wood to use? The
house entrance is covered by the porch overhang 5' deep roof.

My house is very energy efficient, I put a lot of effort into E4
windows and multilayer insulation. So I want to make sure the door
will be well insulated too. What's the best way to insulate it? Make a
door core from closed cell foam insulation? If I put 1" foam between
two 3/4" of wood this would make door 2.5" thick.
Also how to make frame water and draft proof? Any references
preferable with pictures and drawings would be greatly appreciated.