How to orient the GH

Okay, the more I read the more confused I seem to get. Read a book by Ortho last night and on one page it says orient the GH with the long side East / West to get 5 -10 % more sunlight. Then on the next page it says face the long side South for optimum sunlight. Am I making too much of this, is there really a right way to do it? What is it? Thanks for replies. Lots of rain here today in Arkansas. Nanadee

Mine runs east and west. As you can tell by the picture the door opens to the east . I think the reason to run them east and west is so they can receive more sun.

Those are two different ways of saying the same thing. If the long side runs from east to west, then one of the long sides will be facing south. It may make more sense if you draw it on a piece of paper--mark out N/S/E/W compass points on a piece of paper and draw a rectangle for the greenhouse along the E-W axis and you'll see how one long side faces south.

Wow, better get my drafting paper out so I can figure that out. Here in Colorado many profession setups are North south due to the suns intensity. Just thought I'd make things even more confusing;-)

If your GH is square, or nearly square, it just doesn't make that much difference.

Other factors to consider:

If using the GH through the winter, you will want to insulate the north wall. Orient the GH so that the wall to the north is a large one which is easy to insulate (ie tall and flat)

If you have a lot of large joists and beams, they will create shadows. If the shadows run N/S, the shadows will be evenly distributed across the GH.

If you have a solar GH and you are after maximal solar gain, then you already know which side faces south.