Unfortunatley I-Beams beome detatched from time to time in the floors of selfbailing boats. The causes for this problem are many, but over inflation and rotting floor interior are common.
The best fix for this problem is good boat maintenace. Of course if your reading this thats probably not helping your mood.
At Good Water Boatworks we look at these repairs on a case by case basis. It's often less expensive to replace the entire floor than to repair it. Now and then an I-Beam repair comes in that is cost effective to fix. When those times come up Good Water Boatworks has the experience to do the job.
This is an example of an I-Beam repair
This set of pictures shows the before and after images of a floor brought in by High Desert River Outfitters, one of the local whitewater companies in these parts.