Our house is built into a Texas hillside. The bottom floor has the following: Next to the hillside is a retaining wall w/exterior waterproofing paint and 12-foot wide dirt floor crawlspace. The crawlspace has vents to outside at each end. The interior walls are drywall with sheet batting insulation underneath. The insulation is open to the crawlspace. We have had a moisture problem in the crawlspace because of the house gutters. In addition to fixing those I have put two box fans in the crawlspace. Should those fans be placed in any particular relationship to the vents? Also, should we put some barrier material up to prevent moisture from getting in the insulation?