I have a couple of thoughts-Perhaps the obs area could be above some of the stalls? One of the places I ride has that-saves space.
I also would centralize the feed and tack area, but not have 2 tack rooms. To me that is overkill.
Last winter I boarded at a fairly new place-shaped like a "t" Pretty nice layout, actually. The indoor is the stem of the "T". At the top, where they come together in the middle is the main entrance (a people entrance, really), and as you walk in,immediately on the left is the bathroom, down a short hall, the tack room is on the right (with access to main aisle as well as the hall the door is in for convenience). On the left is the h/c wash stall (backs up plumbing to the bathroom, and straight ahead is a double gate to the indoor (which also has a garage door for the cold winter days/nights to keep the barn warmer. Stalls run both sides of the center entrance, on both sides of a double wide aisle, with a garage door at each end for ventilation, as well as another grooming area at each end. THe office is in the house., Feed is at one end of the T, and meds are in a fridge in the tack room, which is heated and cooled. Having the indoor as the stem of the "t" allows access from all 4 sides, 3 to the outside with sliding doors. They usually don't use but 2 of them, but they are there, in case.
Another was shaped like a "U", with the indoor at the bottom of the "U" and the stalls down each side.
Personally, I would also like to see more central access to the arena. I hate having to interupt so many other people to get to the ring if I am all the way at the far end.
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