The rules state that the porch should be constructed at an external doorway .
With respect, I beg to differ on this; the wording of Class D specifically refers to "door" and not "doorway". The word "doorway" could include either the door itself or the opening in which the door and frame are set; the word "door", however, is specific and can only refer to the hinged part.
That's too pedantic
It is pedantic, as for the purpose of the GPDO, door and doorway are the same thing and the intention is the access "doorway"
In your interpretation, I can stick a door anywhere on the face of a wall and build a porch around it
FMT has given the correct interpretation in that a "doorway" is required. And as I said, a doorway will have a door within it, because no houses come without a front door
Oh dear sore loser!
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