A beam perpendicular in the center of the joists, that is supported with posts, would reduce your joists span to 7' making your 2x10s much stronger. That is what INSPECTORD was trying to say.
What is the dimension of this floor to be supported the other way??? If it is relatively short you may not need more than a post at each end, but if it is too long or you don't have much headroom in the garage then you would need to put a post or two in the middle.
another thought about the wires running through the boards now is that you could cut them and put in a few junction boxes. the problem would probably be with your drain pipes though as they usually don't like water running up hill to get out of them.
Just a couple of thoughts
eta: if you could post some pictures from the underside we may have some better suggestions for you
Last edited by hondadrv24; 02-27-2009 at 08:00 PM.
Reason: pictures are always helpful