I just put each document inside a sheet protector and then seal those with clear shipping tape and then place inside my safe.

One thing you need to be careful of with firesafes, the typical firesafe will not protect anything but paper. Sheet protectors, CD's, anything else plastic can melt well below the flash point of paper and below the inside temp point of a plain firesafe. For any electronic backups you need a media safe or a gun safe. I found that a gun safe meets or exceeds the same rating as a media safe but at a much cheaper price per square foot.