To avoid wasting HVAC energy, we build tighter houses and commercial buildings. However, our old-school air leakage and energy waste used to provide some degree of fault-tolerance for rain leakage and for drying construction-soaked foundations and masonry. And oddly, we now see problems caused by humid air air pulled into tight buildings by kitchen exhausts. This workshop shows examples of humidity and moisture problems in tight buildings, and explains how to avoid and fix them.