Thanks for your input! I asked a company that makes goose houses (in Scotland!) and they said:I have four Brown Chinese. The doors are 36" high and 16" wide. I can squeeze in if needed, so I would imagine a larger goose could fit too
Your door will need to be 29" wide and about 28" tall to give them plenty of room.
So, I may split the difference of your two opinions and hope the geese can get their honking big selves in and out!