I had a crack on the basement wall with small amount of water coming in. Epoxy injection had fixed it for almost 4 years. Now i see water reentering again. Can i re-inject epoxy in the same area where epoxy was applied? Should i remove/clean the old injected materials?

[left]I have an existing house that was built in 1953 in the southeastern U.S., Tennessee to be exact where the humidity gets very high in the summer months. The foundation has automatic vents in it with no moisture barrier at all. The ground underneath the house is dry as a bone and hard as concrete. This leads me to the problem, though. In 2007; we added a small addition to the house, 12x24. There is one small opening from the old foundation to the new foundation; just big enough to crawl through to work on a water line if needed. The new foundation for the 12x24 addition does not have any vents in it. The only air that gets to it is from the small opening from the old foundation. Also, there was no moisture barrier put down anywhere in the new addition. In 11 years, the floor joists have rotted due to the excess moisture. We are in the process of repairing the damage. Here are the questions I would like to ask as far a stopping the moisture: 1. I know I need to put down a moisture barrier; what thickness should I use? 2. Should I install vents in the new foundation or should I seal the vents in the old foundation? 3. The new foundation is only about two feet off rhe ground, the drainage is good, should I seal this concrete foundation from the outside in any way? Any other suggestions will be greatly appreciated.[/left]