12 X 12 is ideal, 10 X 10 is workable for small horses. I wouldn't go any smaller than that.
If the dimensions of your building are 24 X 20, you can have 2 stalls and a 10 ft aisle, and you can make a tack storage area of 6 X 10 at one end, free from the swing of the stall door.
If the dimensions of your building are 24 X 20, you can have 2 stalls and a 10 ft aisle, and you can make a tack storage area of 6 X 10 at one end, free from the swing of the stall door.
