I wish I could commute to work like I used to and save on gas, but nowadays its too far and too hilly....and I work 12.5 hour days. These are what I think you should be aware of; your physical condition, your gearing, the route and the hills (if any). If your route is relatively flat and you have mostly bike lanes to use, you're good to go....should be fun and rewarding! Thirteen miles one way is doable riding a fixed gear IF your gearing is reasonable and IF your knees can take it. Hell, I'm an older rider and I ride 15~25 miles/60~90 minutes (depending on route) fixed on my Soho-S for excercise and relaxation...and I just started. Allot yourself a reasonable amount of time to get to your workplace with enough time to change out and punch the clock (if that's what you're required to do) fresh and ready. That's what I used to do....and I saved $$$$ and lost lbs! Next thing you know you're be taking the long way home...you might even look for some hills! Good luck and have fun!