you could probably keep your 180 if you ran perpendicular to the joists. 
 
Honestly, I cant see how any house would be built with 2x6's as floor joists. Arent they always at least 2x10? They were when I was working construction for 2 summers back in high school... 
		
	
		
		
		
		
		
	
		
		
	
	
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