House is located in Albany, NY (northeast US).

On the ground floor of my house, I have two 12' x 25'/30' rooms, that are connected together through two 4' wide openings/doorless doorways (the main support beam of the house runs between the two rooms.

On the left side of the house, the kitchen cabinets run about 23' against the exterior wall, and a large island exists. On the other side of the house (the right side), in the 12'x25' living room, there is a chimney and hearth (hearth is to be flush with the maple floor).

I've read that 5" planks expand quite a bit (solid 3/4" maple), and my question is should I:

1) start at the center of the house and run the boards under/toward the exterior wall, thus hiding the face-nailed boards under the kitchen cabinets (I know there is a lot of arguments about placing hardwood or plywood under the cabinets, but I've already bought the extra flooring for under the cabinets); and run the living room floor from the exterior wall (where the chimney is), and toward the center of the house (and hide the face-nailed boards primarily under the couch that will be in the living room/against the interior wall); or

2) start in the center of each room, add a spline, and run the floors toward the exteriors of each room, meeting in the middle of the house, at the doorways.

Here is a link to an image of the ground floor: http://imgur.com/Vv0qrlN

The HVAC system is running, and the wooden floor have been in the house for months. I've ordered a humidifier and plan to bring the humidity up to 30%, and maintain that year-round.

With that 30% in mind, do I need to add any spacers since I'm installing in winter-time conditions?

Thanks for reading/your advice.