I do think you should make it a tad larger for maneuverability and ventilation purposes. (Oh heck, where's spell check when you need it) :new_shocked:
Holly foaled unfortunately in our old barn. The stalls were 12 X 12.
I thought that would not be large enough. Wrong, wrong wrong.
In the new barn, our stalls are 10 X 10 and mother and baby have more than enough room in there to keep cozy and cuddle up and move around. If I want to, I can remove the wall making it 10 X 20 in about 5 minutes or less. Just simply hasn't been necessary.