Problems

• Condensation from warmer air inside the house can cause moisture to become trapped under a metal roof. This can cause rot, mold and corrosion, according to MetalConstruction.org. Wood, metal parts and insulation can be damaged by the trapped moisture.
  
  

Causes

• Causes of warmer air inside a building include interior heating, humidifiers, plumbing leaks, doing laundry, nonvented fireplaces, cooking and hot water use in showers and baths. The greater the number of occupants in the house and inadequate ventilation can contribute to condensation problems.
  
  

Recommendations

• Recommendations for reducing condensation include venting the attic, venting exhaust fans to the outside of the house and installing a vapor barrier between the ceiling insulation and the interior air to prevent the air from rising into the attic.