I was looking through some of the other bulletin board messages, and I noticed a similar one from a Cam Herman. Iím guessing that he is your husband?
He mentions raising the house. Do you plan to actually lift the house off the foundation in order to repair it? If so, sounds like a really big project. Also, he mentions raising the house to ground level. What does that mean?
In any event, the reason Iím not pushing the French drain idea is because French drains really function to help keep basements dry. The key word here is basements, which are big holes in the ground that mother-nature spends an eternity trying to fill back up, with dirt, water, or whatever is available. Itís simple physics. Water will try to seek the lowest point, so water in soil tends to go to that previously mentioned big hole under the house. The walls keep the dirt out. The drains try to siphon off the water before it seeps into the basement, usually with the help of a sump pump.
Since you do not have a basement, the ground level under the house is about the same as around it, so the urge to fill the hole really isnít there. If the soil under your house is very wet, I would suspect surface water is flowing into your little vents in the foundation. Others would probably disagree, but I suspect the ground under the house is relatively dry, unless you are really close to a lake or something.
If you are really going to raise the house, consider adding another course or two of block along the foundation wall. This will raise the house, allowing the crawlspace to breathe better. Also, install bigger vents, and spend the extra money and replace the sill plates with pressure-treated lumber.