Infrared thermography is a nondestructive technology that can help identify building envelope issues such as wet areas and lack of or inadequate insulation in building envelopes invisible to the human eye. When conducted at the right time of night infrared (IR) inspections can determine which materials are wet or in contact with wet materials and which are dry. This is possible because water has a high specific heat, which means that it stores heat well and cools down more slowly than common roofing materials.